feat(loop): ui_review Stage 5 — lens fan-out + converge

[mfittko]

Part of #1067. Stage 5 of the UI-review-strengthening epic. Depends on: #S1–#S4 (needs the semantic, axe, console, and viewport/interaction inputs).

Summary

Run a11y / layout-geometry / visual / interaction lenses in parallel over one enriched bundle and converge to a deduped findings set, keeping the existing outcome enum and fail-closed contract.

Acceptance criteria

• The four lenses run against one enriched bundle and converge to a deduped set.
• The outcome enum (continue_ui_fix_loop/ui_review_satisfied/blocked_needs_human_decision) and the fail-closed contract are unchanged.
• Dedupe/converge logic is a pure, tested seam.
• npm run verify green.

Non-goals

Acceptance-criterion traceability (Stage 6). Net-new capture inputs.

Unresolved (resolve at stage refinement)

Execution model — sequential passes over one captured bundle vs truly parallel model calls; whether converge/dedupe is a new module or an extension of the existing designer/vision route (RFC-worthy: routing + cost + reuse tradeoff).

[mfittko]

Superseded — Stage 5 shipped under the duplicate issue #1322 (merged as PR #1324): the four lenses (a11y/layout-geometry/visual/interaction) fan out over one enriched named-state bundle and converge to a deduped findings set via a pure, tested seam (scripts/loop/ui-review-lenses.mjs), with the outcome enum and fail-closed contract unchanged. All ACs here are satisfied by that work. Closing as a duplicate.