* feat(workbench-ui): design system v1 scaffold
* fix(workbench): close R1 (GroundingSource enum coverage) + R4 (digest test)
R1 — Promote GroundingSource to a typed Literal in core/epistemic_state.py
so it has the same single-source-of-truth shape as ReviewState. The
existing epistemic_state_for_grounding_source() function already
enumerates the six labels (pack, teaching, vault, partial, oov, none);
this codifies them.
scripts/dump-enums.py now snapshots GroundingSource via the existing
literal_values helper. workbench-ui's enumCoverage.test.ts gains a
fourth assertion that the badge mapping matches the Python source
1:1. Adding a grounding-source value on the Python side without
updating the badge fails the build-time test loud — same discipline
as the other three enums.
R4 — Add an explicit DigestBadge test to StableJsonViewer.test.tsx:
asserts the badge text matches the SHA-256 prefix of the source bytes,
and clicking the badge copies the FULL digest (not the truncated
prefix). Recomputes the expected digest via crypto.subtle to avoid
hard-coding a hex string that could drift.
R2 (component-level reduced-motion enforcement), R3 (EmptyState
copy-CLI affordance), and R5 (`uv run core` packaging paper cut) are
deferred — R2/R3 become meaningful with W-027/W-029, R5 is a
packaging-layer concern outside this PR's scope.
Validation:
- pnpm test: 19 passed (was 17, +1 enum coverage, +1 digest test)
- pnpm build: clean
- pnpm test:enum-coverage: 4 passed
- core test --suite smoke -q: 67 passed
