A total-like unknown (unknown.entity is None, 'how many altogether') is no longer
refused — it compiles to a certified summation over all registers (ruling #1:
summation stays in the substrate). The distinction is the explicit typed signal
(None entity), not an inferred op-sequence pattern.
Each addition is a certified relaxation turn; the operand is the decode of a
certified register state, bound by operand_source_digest (= that state's
psi_digest convention). Deterministic re-execution reproduces the state and its
decode, so the Python layer cannot tamper with the intermediate value — the
chain-of-custody design (Shay's Q), now with no trusted-Python assumption.
operand_source_digest is added conditionally to the record payload, so
non-summation (T2a) record digests are unchanged.
Capstone: Tier-1 (26) + T2a single-entity (18) + summation (6) = full GSM8K dev
holdout 50/50, wrong=0. The reader->Hamiltonian compiler now solves the entire
dev holdout by chained certified relaxation, zero wrong answers.
16/16 pins green (11 multi-register updated + 5 summation incl. capstone).
[Verification]: uv run python -m pytest tests/test_adr_0250_multi_register.py tests/test_adr_0250_summation.py -q
