Feat v0.6.1-v0.6.2: backup/restore, docs surface, dynamic OpenAPI

v0.6.1 — Backup tooling (.swb ZIP export/import), admin backup section,
docs surface with markdown rendering, 5 reference docs, 6 handler tests.

v0.6.2 — Dark mode contrast fixes, topbar nav, 📖 docs icon, dynamic
OpenAPI spec with extension route merging, docs outline sidebar,
scroll/routing fixes; 7 new tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ROADMAP.md

@@ -437,12 +437,29 @@ PG is the consensus layer. Zero new infrastructure. `UNLOGGED` table + `LISTEN/N
 | Single-node regression | ✅ | One-node behavior identical to pre-cluster: one registry row, NOTIFY delivers back to same instance. No special-casing. SQLite returns nil store — all cluster code guarded. |
 | Multi-node integration test | ✅ | Docker Compose: 3 instances, shared PG. `ci/e2e-cluster-test.sh`: registration, stale sweep on stop, re-registration on restart. 3 unit tests + 2 handler tests. |
 
-### v0.6.1 — Backup/Restore + Documentation (planned)
+### v0.6.1 — Backup/Restore + Documentation
 
 | Step | Status | Description |
 |------|--------|-------------|
-| Backup tooling | | ext_data export/import, admin surface for backup management. |
-| Documentation site | | Extension authoring guide, API reference, deployment guide. |
+| Backup handler | ✅ | `POST /api/v1/admin/backup` streams `.swb` ZIP (JSONL core + ext_data tables + package assets). `POST /api/v1/admin/restore` wipes DB and restores from archive. Dialect-neutral (SQLite + Postgres). |
+| Server-side backups | ✅ | `GET /api/v1/admin/backups` list, `GET /download`, `DELETE`. Store backups in `{STORAGE_PATH}/backups/`. |
+| Admin backup section | ✅ | New "Backup" section under `/admin/backup`. Create (download or server-side), list, download, delete, restore with destructive confirmation. |
+| Documentation API | ✅ | `GET /api/v1/docs` lists, `GET /api/v1/docs/:name` returns raw markdown. Authenticated (not admin-only). |
+| Docs surface | ✅ | Builtin surface at `/docs/:section`. Sidebar navigation, client-side markdown renderer. 5 new docs: Getting Started, Extension Guide, API Reference, Deployment, Package Format. |
+| Tests | ✅ | 6 handler tests (basic backup, ext_data backup, round-trip restore, schema mismatch, dump/restore table, list empty). E2E script `ci/e2e-backup-test.sh`. |
+
+### v0.6.2 — Docs Polish + Dynamic OpenAPI
+
+| Step | Status | Description |
+|------|--------|-------------|
+| Dark mode fix | ✅ | Added `--bg-code` to CSS variables (dark + light). Replaced all hardcoded light-mode fallbacks in docs CSS with theme-aware variables. Table styling, code blocks, nav items all readable in dark mode. |
+| Loading & error handling | ✅ | Replaced borrowed `settings-placeholder` with docs-specific pulse animation. Added error state with retry button for failed doc list fetch. |
+| Topbar navigation | ✅ | Imported `Topbar` + `UserMenu` into docs surface. Users can now navigate to other surfaces via the avatar menu. |
+| Docs icon + menu entry | ✅ | Added `📖 Docs` entry to UserMenu standard items. Docs accessible from any surface's user menu. |
+| `api_schema` manifest field | ✅ | Optional `api_schema` array in `manifest.json`. Parsed lazily by spec builder. Malformed entries logged and skipped — never blocks extension loading. |
+| OpenAPI spec builder | ✅ | `BuildOpenAPISpec()` merges static kernel spec with extension routes. Tier 1: auto-generated stubs for all `api_routes`. Tier 2: `api_schema` replaces stubs with rich path items (params, body, response). |
+| Dynamic spec endpoint | ✅ | `GET /api/docs/openapi.json` serves merged spec. Swagger UI updated to use JSON endpoint. Static YAML preserved for backward compat. |
+| Tests | ✅ | 7 new handler tests: zero extensions, stubs, rich schema, multi-extension, malformed schema, disabled exclusion, required fields. |
 
 ## Post-MVP