feat(static-pages): extend data model with route/enabled/status/media/SEO

Milestone 1 of the Static Pages Module sprint.

- StaticPageConfig / ContentPage / ContentPageBootstrapInput gain: explicit
  editable route (defaults from slug, independently overridable), enabled
  (master on/off), status: 'draft'|'published' (per-page publish lifecycle,
  independent of the whole-bootstrap draft/publish cycle), customTemplate,
  heroImage/thumbnail/gallery, and seo.robots.
- ContentPageService: normalizePage/normalizePages default missing
  enabled/status to enabled+published so existing bootstrap data never gets
  silently un-published; only the editor's createPage() opts a brand-new page
  into 'draft'. Legacy array-format pages get the same treatment.
- resolvePage now returns null (storefront 404) for a disabled or draft page,
  regardless of whether the surrounding bootstrap itself is published -
  affects the storefront static-page route AND the auto-generated footer nav
  group (both go through this same resolver), which is the correct behavior.
- validatePages extended: duplicateRoutes (route can now diverge from slug),
  invalidHtml, invalidSeo (canonical/ogImage URL shape, known robots tokens).
- New schema/validators/primitives.validateHtml: stack-based tag-balance
  check (void/self-closing elements skipped, comments stripped). Caught and
  fixed a real bug during its own spec run: the initial implementation popped
  the stack back to the nearest matching ancestor on a mismatched closing
  tag, which silently swallowed a genuinely unclosed inner tag instead of
  flagging it - now a closing tag must match the top of the stack exactly.
- toBootstrapRecord serializes the new fields; visible mirrors enabled so any
  reader of the older field name stays truthful.
- Specs: content-page.service.spec.ts (new), primitives.spec.ts (validateHtml).

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

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

src/app/shared/models/config/static-page.model.ts

@@ -28,6 +28,7 @@ export interface StaticPageTranslationConfig {
     ogTitle?: string;
     ogDescription?: string;
     ogImage?: string;
+    robots?: string;
   };
 }
 
@@ -53,6 +54,14 @@ export interface StaticPageConfig {
   visible?: boolean;
   route?: string;
   content?: LocalizedHtmlContent;
+  /** Master on/off switch. Kept in sync with `visible` on serialize; a disabled page never resolves on the storefront regardless of `status`. */
+  enabled?: boolean;
+  /** Per-page publish lifecycle, independent of the whole-bootstrap draft/publish cycle. A `draft` page never resolves on the storefront even when the surrounding bootstrap is published. */
+  status?: 'draft' | 'published';
+  customTemplate?: string;
+  heroImage?: string;
+  thumbnail?: string;
+  gallery?: string[];
 }
 
 export interface LegacyStaticPageConfig {
@@ -84,4 +93,8 @@ export interface ResolvedStaticPage {
     ogImage?: string;
     robots?: string;
   };
+  customTemplate?: string;
+  heroImage?: string;
+  thumbnail?: string;
+  gallery?: string[];
 }