docs: consolidate documentation and archive temporary reports

Step 1-2 (audit + plan): classified 35 project markdown files into
Core/Architecture/ADR/Temporary-audit/Sprint-report/Generated-review/
Duplicate/Obsolete/Historical. Agent-tooling files (.agents/skills/**,
.superpowers/**, docs/context/**, CLAUDE.md/GEMINI.md/AGENTS.md/
.github/copilot-instructions.md) explicitly out of scope — intentional
per-tool duplication, not documentation debt.

Step 3 (merge, no information lost):
- docs/PROJECT.md -> docs/PROJECT_INDEX.md, rewritten as the single
  entry point: system overview, living-doc index, archive pointer,
  current status, and a critical-finding callout up top.
- docs/backend/BACKEND-INTEGRATION.md -> docs/BACKEND_API.md,
  docs/backend/REMAINING-BACKEND-WORK.md ->
  docs/BACKEND_API_REMAINING_WORK.md (also folded in a legitimate
  uncommitted status update that had been sitting unstaged all
  session: categories marked DONE, order-creation endpoint noted done).
- RELEASE-NOTES.md merged into CHANGELOG.md (was a near-duplicate of
  the same release content in friendlier prose), then deleted.
- KNOWN-ISSUES.md: added item 13 (see below) and item 14 (missing
  canDeactivate on admin/products edit, from the archived PROJECT-STATE
  audit, re-verified still true); added a correction note to Fixed
  item 7.
- All cross-references to renamed/moved files fixed across every
  kept doc (grep+sed pass, then verified with a link-existence check
  across all 58 in-scope markdown files -> 0 broken links).

Step 4 (archive, nothing deleted without merging first): created
docs/archive/, moved 19 files there (3 root sprint reports, 1 platform
report, SPRINT-PLAN.md, and 14 one-off audit/review/report docs).
Added correction headers to the 3 archived docs whose conclusions were
affected by the finding below, rather than silently leaving them
misleading.

Step 5: docs/PROJECT_INDEX.md rewritten per the mission brief -
someone opening the repo should understand the whole system from it.

IMPORTANT FINDING (surfaced during this audit, not the mission's
primary goal but too significant to bury): pages/category/*,
pages/search/*, pages/item-detail/*, pages/info/**, pages/legal/**
(40+ files) are entirely unrouted dead code - app.routes.ts's
cmsContentRoutes is a literal empty array, and category/search/product
routes redirect to CatalogContainerComponent/
ProductDetailsContainerComponent, not these files. Confirmed against
app.routes.ts directly and cross-checked against FRONTEND.md's own
routing description. This means several fixes from earlier this cycle
(RC-Premium-01, RC STORE-01) and the dead-code cleanup sprint's
conclusion that these files were live were all wrong - documented as
KNOWN-ISSUES.md item 13, flagged at the top of PROJECT_INDEX.md, and
noted on the 3 archived docs whose conclusions it affects. No
application code was changed to fix this (out of scope per this
session's 'documentation only' constraint) - it needs a wire-it-up-or-
delete-it decision first.

Verification: tsc --noEmit clean, npm run build green, all markdown
links across 58 in-scope files resolve (checked programmatically).
No application/Angular/backend code modified.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docs/archive/ADMIN_REVIEW.md

@@ -0,0 +1,74 @@
+# Admin UI Polish — RC1 Review
+
+Scope: production-ready UI/UX polish pass across the admin area, one page at a time.
+Architecture, routing, facades, providers, APIs, and data models were left unchanged
+per instructions. No `docs/DESIGN.md` exists in this repo (confirmed during the
+storefront pass), so no page could be checked against it literally; polish decisions
+here follow the shared component library (`app-button`, `app-table`, `app-empty-state`,
+`app-skeleton`, `app-badge`, `app-card`, `app-toggle`) and existing conventions instead.
+
+## Pages reviewed
+
+| Page | Commit | Status |
+|---|---|---|
+| Dashboard | — | reviewed, no changes needed |
+| Marketplace Builder | `fix(admin): polish marketplace-builder` | done |
+| Products | `fix(admin): polish products` | done |
+| Categories | `fix(admin): polish categories` | done |
+| Orders | `fix(admin): polish orders` | done |
+| Customers | — | reviewed, no changes needed |
+| Reviews (moderation) | `fix(admin): polish reviews` | done |
+| Reports | — | reviewed, no changes needed |
+| Transactions | — | reviewed, no changes needed |
+| Analytics | — | reviewed, no changes needed |
+| Monitoring | — | reviewed, no changes needed |
+| Media | — | reviewed, no changes needed |
+| Settings | — | no implementation exists (see backlog) |
+| Diagnostics | — | reviewed, no changes needed (dev-only, excluded from production) |
+
+## Fixes
+
+**Dead code:**
+- Marketplace Builder: removed an unused `ButtonComponent` import/registration from
+  `ProjectEditorHomepageSectionComponent` — it was never referenced in the template
+  and had been silently flagged by every single build (`NG8113` warning) until now.
+
+**Accessibility — recurring pattern across list pages:**
+
+The admin list pages (Products, Categories, Orders, Reviews) share a common
+table-view layout: a "select all" checkbox in the header and a per-row checkbox in
+each `<tr>`. In every one of these tables, **the table view's checkboxes had no
+accessible name** — a screen reader announced only "checkbox, not checked" with no
+indication of what it selects. Notably, the **grid-view equivalent on the same pages
+already had `aria-label`** (e.g. product name, category title, customer name), so this
+was an inconsistency introduced when the table view was built, not a project-wide gap.
+
+Fixed identically across all four:
+- Products: `adminProducts.selectAllRows` / `selectRow`
+- Categories: `adminCategories.selectAllRows` / `selectRow` — plus the per-row
+  **visibility-toggle** checkbox, whose `<label>` wrapped only the input with no text
+  content at all (empty accessible name), got `adminCategories.toggleVisibility`
+- Orders: `adminOrders.selectAllRows` / `selectRow` (row label includes order number)
+- Reviews: `adminModeration.selectAllRows` (row checkbox already had a label via
+  `review.customerName`, only select-all was missing)
+
+All new keys added across `en`/`ru`/`hy`.
+
+## Remaining backlog
+
+- **Settings**: `src/app/features/backoffice/settings/` contains only a `.gitkeep` —
+  no component, no route. Nothing to polish until the feature is built. (Same
+  situation as Checkout in the storefront pass.)
+- Dashboard, Customers, Reports, Transactions, Analytics, Monitoring, Media, and
+  Diagnostics were already in good shape at review time — consistent use of shared
+  components, existing `:focus-visible` coverage on their buttons, empty/loading
+  states already using `app-empty-state`/`app-skeleton`. No action items logged for
+  these; re-review if they're touched again after backend integration lands new UI.
+- The select-all/row-checkbox accessible-name gap was fixed everywhere it was found
+  in this pass (Products/Categories/Orders/Reviews). If any future admin list page is
+  built from the same table pattern, carry the `aria-label` over from day one rather
+  than relying on a follow-up audit to catch it.
+- No `docs/DESIGN.md` exists for either the storefront or admin area. If literal
+  design-system enforcement (type ramp, radius scale, color palette) is wanted going
+  forward, author that file — `impeccable` hook findings are currently checked against
+  a document that doesn't exist.