docs(static-pages): backoffice redirect + StaticPages.md

Milestone 7 of the Static Pages Module sprint.

- app.routes.ts: /backoffice/static-pages now redirects to /edit/static-pages
  (absolute redirectTo) instead of rendering BackofficeComingSoonPageComponent
  - Static Pages is a first-class Project Editor module, not a second CRUD
    surface over the same bootstrap.staticPages data.
- New docs/StaticPages.md: full field reference (General/Localization/SEO/
  Media/Publishing), the enabled+status storefront-gating story and its
  backward-compat default (existing/legacy data normalizes to
  enabled+published so nothing gets silently un-published; only new pages
  default to draft), CRUD/search/filter/bulk, the "mutate from the
  unfiltered list" implementation note, rich-text/HTML-mode contract
  (pointer to EDITOR.md), nav integration, and the export/import/draft/
  publish compatibility statement.
- docs/EDITOR.md: Static Pages row in the Sections table (was previously
  absent - the row lived implicitly in Footer's description), HTML editor
  section updated with the Sprint X+2 toolbar additions + validation
  contract, redirect noted near the route line. `docs/Project-Editor.md`
  (named in the original brief) no longer exists - superseded by EDITOR.md
  per that file's own header; documentation went there + the new file
  instead.
- docs/PROJECT.md: doc index entry for StaticPages.md.

Gate: tsc --noEmit, npm test (57/57), arch:check, build all green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/app.routes.ts

@@ -87,9 +87,12 @@ const coreRoutes: Routes = [
         canDeactivate: [adminCategoryDirtyGuard]
       },
       {
+        // Static Pages is a first-class Project Editor module (Sprint X+2), not a
+        // separate backoffice CRUD surface - redirect here rather than build a
+        // second UI over the same bootstrap.staticPages data.
         path: 'static-pages',
-        loadComponent: () => import('./features/backoffice/shared/backoffice-coming-soon-page.component').then(m => m.BackofficeComingSoonPageComponent),
-        data: { titleKey: 'dashboard.actionStaticPages' }
+        redirectTo: '/edit/static-pages',
+        pathMatch: 'full'
       },
       {
         path: 'transactions',