feat(narrative): responsive layout drawers and complete test suite

[lark-x]

Summary

• Upgraded \NarrativeWorkbenchLayout.vue\ to support responsive slide-out drawers on smaller viewports with backdrops.
• Created 5 comprehensive Narrative Workbench automated test suites in \�pps/web/src/v2/narrative-workbench/tests/:
  1. 
     evision-flow.test.ts\ (Revision CAS monotonic chain advance, collision detection & idempotency keys)
  2. \scene-navigation.test.ts\ (Dirty Draft state machine & navigation guard)
  3. \scene-race.test.ts\ (Generation token cancellation, AbortSignal propagation & race protection)
  4. \quest-flow.test.ts\ (Quest-Local flow graphs, choices connectivity & cross-quest isolation)
  5. \candidate-review.test.ts\ (Multi-dimensional candidate diff & targeted approval)
• Updated \docs/PROGRESS.md.