W7: Possibilities matrix (work-already-done fast path) (#522)

* [W7] Add possibilities_matrix_enabled feature flag (default off)

* [W7] Add _work_appears_done predicate (status+commits+PR+ACs+no-open-findings)

* [W7] Add CI-green quality proxy for the fast path (local fallback on no-CI)

* [W7] Add work-already-done fast path in i_am_done (slimmed gates, no rich plan)

* [W7] Add WORK_ALREADY_DONE prompt state

* [W7] Make fast path mypy-clean (cast to helpers for _resolve_ci_status; typed mock locals)

* [W7] Extract _all_criteria_addressed to bring _work_appears_done under xenon B

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Co-authored-by: Renn F <rennf93@users.noreply.github.com>

panel/src/components/settings/feature-flags-card.tsx

@@ -51,6 +51,8 @@ const FLAG_DESCRIPTIONS: Record<string, string> = {
     "Provision each agent workspace with the target project's Python (not RoboCo's) and block delivery gates when its test suite can't be executed.",
   conventions_enabled:
     "Enforce a per-project architectural standard (.roboco/conventions.yml): inject the map, attach baseline constraints, and block i_am_done / pr_pass on misplaced definitions or lint suppressions.",
+  possibilities_matrix_enabled:
+    "When a task's work is already done (commits + open PR + all acceptance criteria addressed + no open findings), submit it for QA in one i_am_done call instead of 3-6 turns — skips the retroactive plan, journal tracing, and local quality (CI-green proxy) gates. Off by default: the standard path is unchanged until you arm this.",
   rag_auto_update_enabled:
     "Keep the knowledge base index refreshed automatically.",
   transcript_prune_enabled: