docs(adr): land Third-Door Super-Blueprint + ADR-0238/0239/0240 (refs #10 #11 #12 #13)

Canonical ADRs under docs/adr/; thin redirects under docs/decisions/ for
Issue #10 path compatibility. Documents dual GoldTether ontology, residual
namespaces, HITL curve, and Spin left-composition blend geodesic.

Base: forgejo/main @ dbd44a2a

docs/adr/ADR-0238-GoldTether-Modulated-Supervised-Autonomy.md

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+# ADR-0238: GoldTether-Modulated Supervised Autonomy + Dynamic Pseudoscalar Floor
+
+**Status:** Proposed  
+**Date:** 2026-07-11  
+**Branch:** `r&d/generalized-agent`  
+**Parent tracking:** [#10](https://core-gitquarters.acbcontent.org/core-labs/core/issues/10) · Issue [#11](https://core-gitquarters.acbcontent.org/core-labs/core/issues/11)  
+**Owners:** CORE Labs / R&D  
+**Canonical path:** `docs/adr/` (not historical `docs/decisions/`)
+
+**Related:**
+
+- ADR-0010 Identity Physics
+- ADR-0006 Field Energy (distinct residual namespace)
+- ADR-0055 / ADR-0056 / ADR-0080 Contemplation + reviewed promotion
+- ADR-0175 Calibrated Attempt-and-Eliminate
+- ADR-0199 Cross-Domain Learning Arena (`GoldTether` *protocol* — different contract)
+- ADR-0239 Conformal Procrustes + Surprise Dual
+- ADR-0240 Analogical Transfer + Biography Holonomy
+
+**Depends on:** Cl(4,1) closure (`algebra/versor.py`), manifold slerp (`algebra/rotor.py`)
+
+**Acceptance path:** green `tests/test_adr_0238_goldtether.py` + smoke/algebra lanes + Josh review.
+
+---
+
+## 1. Context
+
+CORE needs a **coherence tether** that modulates autonomy without violating HITL defaults, one-mutation-path review, or algebraic closure. Issue #10/#11 name this the GoldTether-modulated supervised autonomy envelope with a dynamic grade-5 pseudoscalar floor.
+
+### Dual ontology (mastery refinement)
+
+| Name | ADR | Contract |
+|---|---|---|
+| **Arena GoldTether** | ADR-0199 | `is_correct` / `gold_answer` — independent truth for practice scoring |
+| **Coherence GoldTether** | **this ADR** | residual + dynamic floor + practice/serve autonomy bands |
+
+Shared metaphor (gold as anchor). **Different types, different modules.** Implementation lives in `core/physics/goldtether.py` as `GoldTetherMonitor` / `CoherenceResidual` — never shadows `core.learning_arena.protocols.GoldTether`.
+
+### Problem
+
+Without a geometric autonomy envelope, either:
+
+1. autonomy is premature (unsafe serve-path self-action), or  
+2. supervision is unstructured (no residual, no floor, no dual-correction blend).
+
+---
+
+## 2. Decision
+
+### 2.1 Harmonized residual
+
+```text
+drift            = |ps(current) − ps(reference)|  (grade-5 / magnitude)
+geometric_distance = || reverse(ref) * current − 1 ||_F
+combined         = w_drift * drift + (1 − w_drift) * normalize(geo)
+kappa            = 1 / (1 + combined / floor)     # monotone; scales blend only
+```
+
+Named config only: `decay_N`, `w_drift`, `floor_init`, `critical_ratio`, `practice_autonomy_enabled`, `serve_supervised_blend_authorized`.
+
+**Residual namespaces (non-negotiable):**
+
+- ADR-0006 `EnergyProfile.coherence_residual` — thermodynamic class input  
+- ADR-0238 `CoherenceResidual.combined` — autonomy tether  
+- ADR-0239 `procrustes_residual` / surprise residual — structural transfer  
+
+Do not conflate.
+
+### 2.2 Dynamic pseudoscalar floor
+
+- Initialized at `floor_init` (primal retained forever under decay).
+- Updated **only** on practice successes with residual < current floor.
+- Decay window `decay_N` keeps recent residuals; floor never drops below half primal.
+- Serve mode never promotes the floor.
+- Telemetry schema: `goldtether_coherence_v1` (value, sign, n_samples, recent_residuals, config).
+
+### 2.3 Autonomy envelope
+
+| Band | Condition | Practice | Serve |
+|---|---|---|---|
+| `AUTONOMOUS` | R < floor | only if `practice_autonomy_enabled` | **never** |
+| `SUPERVISED_BLEND` | R ≤ critical | default below/mid band | only if `serve_supervised_blend_authorized` |
+| `FAIL_CLOSED` | R > critical or serve default | yes | **default** |
+
+HITL phase-out is a **measured curve**, not a flag flip. Self-review gates are documented; they are not auto-proven by this ADR.
+
+### 2.4 Supervised blend (dual-correction)
+
+```text
+R = word_transition_rotor(source, target)   # = target * reverse(source)
+R^α = rotor_power(R, α)
+out = R^α * source                          # Spin left-composition
+assert versor_condition(out) < 1e-6
+# α=0 → source; α=1 → target (unit versors)
+```
+
+**Mastery correction:** sandwich conjugation `R^α * source * reverse(R^α)` is the wrong geodesic for *state* interpolation (it maps the identity to itself). Left composition on the rotor group is the dual-correction surface that lands exactly on the endpoints.
+
+No Euclidean lerp on multivector coefficients. No hot-path unitize repair.
+
+### 2.5 Implementation surface
+
+- Module: `core/physics/goldtether.py`
+- Types: `GoldTetherConfig`, `CoherenceResidual`, `AutonomyBand`, `AutonomyDecision`, `PseudoscalarFloorState`, `GoldTetherMonitor`, `OperatingMode`
+- Proof tests: `tests/test_adr_0238_goldtether.py`
+
+---
+
+## 3. Consequences
+
+### Positive
+
+- Geometry-first autonomy modulation without stochastic fallback.
+- Serve remains fail-closed by default (HITL preserved).
+- Pseudoscalar floor is a first-class telemetry channel for lifelong coherence curves.
+- Explicit dual ontology prevents Arena vs Coherence confusion under review.
+
+### Risks / mitigations
+
+| Risk | Mitigation |
+|---|---|
+| Residual conflation with energy residual | Distinct type names + ADR text + tests |
+| Premature autonomy | `practice_autonomy_enabled=False` default; serve never autonomous |
+| Drift repair disguised as blend | Blend only via `rotor_power` / transition rotors |
+
+### Non-goals
+
+- Auto-promotion of SPECULATIVE → COHERENT
+- Replacing ADR-0199 arena GoldTether
+- Approximate recall or sampling
+
+---
+
+## 4. Proof obligations
+
+- **G-1** Replay: identical (current, reference, config, sequence) → identical residual/floor/decision telemetry.
+- **G-2** Closure: every `supervised_blend` output has `versor_condition < 1e-6`.
+- **G-3** Serve never returns `AUTONOMOUS`.
+- **G-4** Floor updates only on practice success below floor.
+- **G-5** Arena GoldTether protocol tests remain green unchanged.

docs/adr/ADR-0239-Conformal-Procrustes-Surprise-Dual-Operator.md

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+# ADR-0239: Conformal Procrustes + Surprise Residual Dual Operator
+
+**Status:** Proposed  
+**Date:** 2026-07-11  
+**Branch:** `r&d/generalized-agent`  
+**Parent:** [#10](https://core-gitquarters.acbcontent.org/core-labs/core/issues/10) · Issue [#12](https://core-gitquarters.acbcontent.org/core-labs/core/issues/12)  
+**Canonical path:** `docs/adr/`
+
+**Related:** ADR-0013 Sensorium · ADR-0198/0209 Sensorimotor · ADR-0238 Coherence GoldTether · ADR-0240 Transfer Harness · ADR-0237 GeometricDelta ABI
+
+**Acceptance path:** green `tests/test_adr_0239_*.py` + algebra lane + Josh review.
+
+---
+
+## 1. Context
+
+Generalized agentic intelligence requires **structural analogy** (transport a solved map into a novel domain) and **boundary sensing** (what is not yet spanned by known structure) without statistical crutches, sampling, or confabulation.
+
+Issue #12 specifies:
+
+- Signature-aware Conformal PCA with null-vector classification  
+- Conformal Procrustes (versor search for structural analogy)  
+- Surprise Residual `S(x) = x − proj_B(x)`  
+- Dual: high surprise seeds Procrustes against vault analogs → productive novelty  
+
+### Mastery refinements closed here
+
+1. **Null vectors never silently skipped** — every axis classified (`SPACELIKE|TIMELIKE|NULL|DEGENERATE`) and counted.  
+2. **Dedicated `procrustes_residual` norm** — not null-margin, not energy residual, not GoldTether combined residual.  
+3. **κ from ADR-0238** scales productive threshold only — never invents content.  
+4. **Cartan–Iwasawa constructive factorization** supplies the dual-correction surface for factor-wise slerp.
+
+---
+
+## 2. Decision
+
+### 2.1 Signature-aware PCA
+
+Module: `core/physics/dynamic_manifold.py` → `signature_aware_pca`.
+
+- Metric on grade-1: Cl(4,1) signature `(+,+,+,+,-)`.  
+- Higher grades: positive definite on coefficients (classification sense).  
+- Metric-rescaled covariance + symmetric `eigh` (deterministic order).  
+- Eigenvector sign convention: first nonzero component positive.  
+- **All axes returned** including NULL.
+
+### 2.2 Conformal Procrustes
+
+`conformal_procrustes(sources, targets) → ConformalProcrustesResult`
+
+- Single pair: `word_transition_rotor(s, t)`.  
+- Multi pair: sequential manifold average (equal-weight geodesic midpoints in input order).  
+- Output versor must satisfy `versor_condition < 1e-6`.  
+- Residual: `procrustes_residual(s, t, V) = ||V s reverse(V) − t||_F`.
+
+### 2.3 Cartan–Iwasawa factors
+
+`cartan_iwasawa_factorize(V) → K, A, N` with reconstruction residual.
+
+- Simple rotation (`B² < 0`) → K  
+- Simple boost (`B² > 0`) → A  
+- Null / residual → N  
+- `dual_correction_slerp` powers factors independently then recomposes.
+
+### 2.4 Surprise Residual + dual
+
+Module: `core/physics/surprise.py`
+
+```text
+S(x) = x − proj_B(x)     # orthonormal span of ordered basis
+affinity(analog) = |cos|(S, target−source)
+dual: best analog → Procrustes; productive iff residual ≤ threshold/κ
+```
+
+No sampling. Ordered analog list; stable sort by affinity desc, id asc.
+
+---
+
+## 3. Consequences
+
+### Positive
+
+- Structural transfer without embeddings-as-truth.  
+- Explicit null classification closes a long-standing silent-drop hazard.  
+- Dual operator converts surprise into *proposal-grade* novelty only when residual-proven.
+
+### Risks
+
+| Risk | Mitigation |
+|---|---|
+| PCA treated as memory truth | PCA is analysis/telemetry only; vault recall remains exact CGA |
+| Non-simple versor average drift | unitize only at construction boundary; fail residual loudly |
+| Confabulated analogy | productive=False → refuse / NOT_YET path (ADR-0240) |
+
+### Non-goals
+
+- ANN / cosine vault recall  
+- Stochastic exploration  
+- Motor actuation  
+
+---
+
+## 4. Proof obligations
+
+- **P-1** Null axes present in result counts when constructed.  
+- **P-2** Procrustes output closed.  
+- **P-3** Surprise residual orthogonal to basis span (within tol).  
+- **P-4** Dual replay byte-identical for identical inputs.  
+- **P-5** Cartan–Iwasawa factors each closed.

docs/adr/ADR-0240-Analogical-Transfer-Validation-Harness-Biography-Holonomy.md

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+# ADR-0240: Analogical Transfer Harness + Biography Holonomy + Temporal Gate + Self-Authorship Miner
+
+**Status:** Proposed  
+**Date:** 2026-07-11  
+**Branch:** `r&d/generalized-agent`  
+**Parent:** [#10](https://core-gitquarters.acbcontent.org/core-labs/core/issues/10) · Issue [#13](https://core-gitquarters.acbcontent.org/core-labs/core/issues/13)  
+**Canonical path:** `docs/adr/`
+
+**Related:** ADR-0010 Identity · ADR-0055/0080 Contemplation · ADR-0150/0151 Proposal corridor · ADR-0199 Arena · ADR-0238/0239 Third Door operators
+
+**Acceptance path:** green `tests/test_adr_0240_*.py` + harness wrong=0 on fixture pair + Josh review.
+
+---
+
+## 1. Context
+
+Operators alone do not prove generalized agency. This ADR lands the **genius layer** that binds them to lifelong identity and safe proposal discipline:
+
+1. **Analogical Transfer Validation Harness** — solved domain → novel domain under residual measurement + wrong=0  
+2. **Biography Holonomy Blade** — forever-lived individuality as reconstructible holonomy  
+3. **Temporal Admissibility Gate** — wisdom as geometry (`ADMIT` / `NOT_YET` / `REFUSE`)  
+4. **Self-Authorship Miner** — geometry-guided **proposal-only** extensions  
+
+### Mastery refinements
+
+- Biography is **recompute-from-trajectory**, not raw experience storage (reconstruction-over-storage).  
+- Temporal gate never confabulates early — typed `NOT_YET` disclosures.  
+- Miner emits `epistemic_status=SPECULATIVE` only; zero vault writes; stable proposal_id ordering.  
+- Harness is pytest-first; Tier-2 CLAIMS pin deferred until green history exists (do not hand-edit `CLAIMS.md`).
+
+---
+
+## 2. Decision
+
+### 2.1 Analogical transfer harness
+
+Path: `evals/analogical_transfer/harness.py`
+
+```text
+learn V = conformal_procrustes(source → target)
+mapped = V * novel_query * reverse(V)
+residual = ||mapped − expected||
+wrong++ if residual > threshold and not refused
+```
+
+Fixture pair: rotation structural transfer across domains (`make_fixture_pair`).
+
+### 2.2 Biography Holonomy Blade
+
+Path: `core/physics/biography.py`
+
+- `integrate_biography(trajectory)` → `BiographyHolonomyBlade` via `holonomy_encode`  
+- Order is load-bearing; empty trajectory refused  
+- Telemetry schema `biography_holonomy_v1` (hash, steps, closure, scalar/pseudoscalar projections)
+
+### 2.3 Temporal Admissibility Gate
+
+Path: `core/physics/temporal_gate.py`
+
+Pure predicate over `TemporalContext` (step, min_step, evidence counts, residual ceiling, prerequisites). Returns typed disclosure payloads suitable for epistemic surfaces.
+
+### 2.4 Self-Authorship Miner
+
+Path: `core/physics/self_authorship.py`
+
+- Inputs: current/reference versors, optional basis + analogs  
+- Outputs: ordered `AuthorshipProposal` tuples with `drift_residual` + `closure_proof`  
+- **Never** calls `VaultStore.store`; promotion remains ADR-0151 / review corridor  
+
+---
+
+## 3. Consequences
+
+### Positive
+
+- Lifelong identity strengthened via reconstructible holonomy.  
+- Transfer claims become falsifiable (wrong=0 harness).  
+- Self-extension stays proposal-only (INV-21/22/23 spirit).  
+
+### Risks
+
+| Risk | Mitigation |
+|---|---|
+| Biography used as memory dump | hash + holonomy only; no raw transcript storage |
+| Miner auto-serve | SPECULATIVE only; no serving path import |
+| Premature claim emission | Temporal gate NOT_YET |
+
+### Non-goals
+
+- Physical motor decode  
+- Auto-accept proposals  
+- CLAIMS Tier-2 pin in this PR  
+
+---
+
+## 4. Proof obligations
+
+- **H-1** Fixture transfer wrong=0 under threshold.  
+- **H-2** Biography reconstructible and order-sensitive.  
+- **H-3** Temporal NOT_YET before min_step / insufficient evidence.  
+- **H-4** Miner proposals all SPECULATIVE; deterministic id order.  
+- **H-5** No module imports vault store for mutation.

docs/decisions/ADR-0238-GoldTether-Modulated-Supervised-Autonomy.md

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+# ADR-0238 — Redirect
+
+**Canonical location:** [`docs/adr/ADR-0238-GoldTether-Modulated-Supervised-Autonomy.md`](../adr/ADR-0238-GoldTether-Modulated-Supervised-Autonomy.md)
+
+`docs/decisions/` is historical. All new ADR content lives under `docs/adr/`.
+This stub exists so Issue #10/#11 paths resolve without duplicating the decision record.

docs/decisions/ADR-0239-Conformal-Procrustes-Surprise-Dual-Operator.md

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+# ADR-0239 — Redirect
+
+**Canonical location:** [`docs/adr/ADR-0239-Conformal-Procrustes-Surprise-Dual-Operator.md`](../adr/ADR-0239-Conformal-Procrustes-Surprise-Dual-Operator.md)
+
+`docs/decisions/` is historical. All new ADR content lives under `docs/adr/`.
+This stub exists so Issue #10/#12 paths resolve without duplicating the decision record.

docs/decisions/ADR-0240-Analogical-Transfer-Validation-Harness-Biography-Holonomy.md

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+# ADR-0240 — Redirect
+
+**Canonical location:** [`docs/adr/ADR-0240-Analogical-Transfer-Validation-Harness-Biography-Holonomy.md`](../adr/ADR-0240-Analogical-Transfer-Validation-Harness-Biography-Holonomy.md)
+
+`docs/decisions/` is historical. All new ADR content lives under `docs/adr/`.
+This stub exists so Issue #10/#13 paths resolve without duplicating the decision record.

docs/decisions/README.md

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+# Historical ADR path
+
+New ADRs **must** be written under [`docs/adr/`](../adr/README.md).
+
+This directory remains only for historical links and **redirect stubs** that
+point auditors from legacy issue paths (e.g. Third-Door Issues #10–#13) to the
+canonical `docs/adr/` files.
+
+| Legacy / issue path | Canonical |
+|---|---|
+| `docs/decisions/ADR-0238-…` | [`docs/adr/ADR-0238-GoldTether-Modulated-Supervised-Autonomy.md`](../adr/ADR-0238-GoldTether-Modulated-Supervised-Autonomy.md) |
+| `docs/decisions/ADR-0239-…` | [`docs/adr/ADR-0239-Conformal-Procrustes-Surprise-Dual-Operator.md`](../adr/ADR-0239-Conformal-Procrustes-Surprise-Dual-Operator.md) |
+| `docs/decisions/ADR-0240-…` | [`docs/adr/ADR-0240-Analogical-Transfer-Validation-Harness-Biography-Holonomy.md`](../adr/ADR-0240-Analogical-Transfer-Validation-Harness-Biography-Holonomy.md) |

docs/research/CORE-ASI-Super-Blueprint-Third-Door-Horizon.md

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+# CORE ASI Super-Blueprint — Third-Door Horizon
+
+**Status:** R&D blueprint (programmatic land on `r&d/generalized-agent`)  
+**Date:** 2026-07-11  
+**Tracking:** Issues #10–#13 · ADR-0238 · ADR-0239 · ADR-0240  
+**Mode:** Geometry-first. No statistical crutches. No sampling. No confabulation.
+
+---
+
+## 1. North star
+
+```text
+listen → comprehend → recall → think → articulate → learn (reviewed) → replay
+```
+
+The Third Door extends this path with **structural analogy**, **coherence-tethered autonomy**, and **lifelong biography holonomy** — without leaving the Cl(4,1) substrate or the review-gated mutation corridor.
+
+---
+
+## 2. Axioms (non-negotiable)
+
+1. Cl(4,1) multivector versors `[f32|f64; 32]`  
+2. Algebraic closure: `versor_condition(F) < 1e-6`  
+3. Dual-correction (factor slerp / transition rotors — not Euclidean lerp)  
+4. Replay-determinism (byte-identical traces)  
+5. One-mutation-path + review gates  
+6. Reconstruction-over-storage  
+7. Forever-lived single trajectory / biography holonomy  
+
+Pillars: **GoldTether coherence**, **Practice vs Serve risk-reward physics**, **Epistemic elevation only through articulate reason + contemplation**.
+
+HITL phase-out only after proven safe self-review — not in this land as a flip switch.
+
+---
+
+## 3. Dual GoldTether ontology
+
+| Sense | Module | Role |
+|---|---|---|
+| Arena GoldTether (ADR-0199) | `core/learning_arena` | Independent truth for practice scoring |
+| Coherence GoldTether (ADR-0238) | `core/physics/goldtether.py` | Residual + dynamic pseudoscalar floor + autonomy bands |
+
+Do not unify the types. Do not shadow names.
+
+---
+
+## 4. Operator algebra (landed modules)
+
+### 4.1 Coherence GoldTether — `core/physics/goldtether.py`
+
+```text
+measure → CoherenceResidual(drift, geo, combined, kappa)
+update_floor → PseudoscalarFloorState   # practice success only
+decide → AutonomyBand                   # serve never AUTONOMOUS by default
+supervised_blend → closed versor        # rotor_power slerp
+telemetry → goldtether_coherence_v1
+```
+
+Bands: `AUTONOMOUS | SUPERVISED_BLEND | FAIL_CLOSED`  
+Critical: `floor * critical_ratio`  
+Config names only: `decay_N`, `w_drift`, `floor_init`, `critical_ratio`, `practice_autonomy_enabled`, `serve_supervised_blend_authorized`.
+
+### 4.2 Dynamic manifold — `core/physics/dynamic_manifold.py`
+
+```text
+signature_aware_pca      # null axes classified, never dropped
+conformal_procrustes     # versor map; dedicated residual norm
+cartan_iwasawa_factorize # K, A, N dual-correction surface
+dual_correction_slerp    # factor-wise power then recompose
+```
+
+### 4.3 Surprise dual — `core/physics/surprise.py`
+
+```text
+S(x) = x − proj_B(x)
+analogy_seed → ordered affinities
+dual_operator → productive novelty iff residual ≤ threshold/κ
+```
+
+### 4.4 Genius layer — ADR-0240
+
+| Module | Role |
+|---|---|
+| `core/physics/biography.py` | Biography Holonomy Blade (recompute) |
+| `core/physics/temporal_gate.py` | ADMIT / NOT_YET / REFUSE |
+| `core/physics/self_authorship.py` | SPECULATIVE proposals only |
+| `evals/analogical_transfer/harness.py` | Transfer validation, wrong=0 |
+
+---
+
+## 5. Practice vs Serve physics
+
+```text
+PRACTICE: residual learning + optional autonomy when enabled + floor updates
+SERVE:    fail-closed default; supervised blend only if explicitly authorized
+```
+
+Risk-reward: practice earns evidence; serve may not invent authority.
+
+---
+
+## 6. Lifelong coherence telemetry
+
+Required channels (pure projections; workbench-consumable):
+
+1. **Pseudoscalar floor** — `GoldTetherMonitor.telemetry()`  
+2. **Manifold projection** — PCA axis classifications + explained fractions  
+3. **Biography holonomy** — `biography_telemetry()`  
+
+Do not break existing workbench contracts; additive only.
+
+---
+
+## 7. Sensorimotor note
+
+Afferent sensorimotor (ADR-0209) and efferent gates (ADR-0198) remain as-is. This land does **not** mount physical decoders. Cartan–Iwasawa paths are zero-fabrication algebraic scaffolds for future trajectory operators.
+
+Rust parity (`core-rs`) deferred until Python operators are sealed.
+
+---
+
+## 8. Invariants preserved
+
+- No cosine/ANN/HNSW as runtime memory truth  
+- No stochastic generation on cognitive path  
+- No drift-repair unitize outside construction boundaries  
+- No unreviewed durable mutation  
+- Arena practice engine unchanged  
+
+---
+
+## 9. Validation
+
+```bash
+python -m pytest tests/test_adr_0238_goldtether.py tests/test_adr_0239_*.py tests/test_adr_0240_*.py -q
+core test --suite smoke -q
+core test --suite algebra -q
+```
+
+---
+
+## 10. Mastery refinements vs original sandbox artifacts
+
+1. ADR path corrected to `docs/adr/` (canonical); thin redirects under `docs/decisions/` for Issue #10 path compatibility.  
+2. Dual GoldTether ontology made explicit and non-colliding.  
+3. Residual namespaces separated (energy / coherence / procrustes / surprise).  
+4. Null PCA classification mandatory with counts.  
+5. Serve autonomy hard-blocked; HITL default documented as curve not switch.  
+6. Biography as reconstructible holonomy only.  
+7. Miner proposal-only with stable content hashes.  
+8. Branch rebased onto current Forgejo `main` before land.  
+9. **Supervised blend / dual-correction slerp use Spin left-composition**  
+   `out = rotor_power(R, α) * source` (not sandwich conjugation). Sandwich maps the identity to itself and is the wrong geodesic for state interpolation; endpoints are exact (α=0→source, α=1→target).
+
+This is the single right solution for the Third-Door Horizon layer.