docs(phase2): reconcile requirements and migrate capabilities/contracts

Surface-matrix sweep of every source doc; added nine missed behaviors (METADATA-115, REVIEW-50, APP-55/60/65, SETTINGS-45 mode, Generate-text availability, defaults-off). 153 requirements, 0 coverage gaps.

Migrated capabilities to docs/capabilities/ and contracts to docs/contracts/; added WOO-API, API, DATA-MODEL, PROMPTS, UX, TEST-SPEC. Populated MILESTONES; branch-neutral trunk docs; renamed umbrella term to Woo Slab Taxonomy. Archived reconciliation working records under .audit/archive/.

README.md

@@ -12,9 +12,9 @@ Start at [`docs/README.md`](docs/README.md) for goals, what already shipped, and
 | Milestones (ID subsets) | `docs/MILESTONES.md` |
 | Product overview | `docs/PRODUCT.md` |
 | Invariants and agent context | `AGENTS.md` |
-| Milestone 1 Capture (shipped) | `docs/CAPTURE.md` |
-| Milestone 2 Photos (shipped) | `docs/PHOTOS.md` |
-| Milestone 3 Create (paused — requirements reconciliation) | `docs/CREATE.md` |
+| Milestone 1 Capture (shipped) | `docs/capabilities/CAPTURE.md` |
+| Milestone 2 Photos (shipped) | `docs/capabilities/PHOTOS.md` |
+| Milestone 3 Create (paused — requirements reconciliation) | `docs/capabilities/CREATE.md` |
 | UAT practice walk | `docs/UAT-PRACTICE.md` |
 | Hosting | `deploy/` |