Engagament rename; redirects installed, CLI-queued and backfilled

- new generic vitec:rename-page --page=<uid|slug> --title="...": renames
  a page, recalculates its own slug from the parent slug plus the new
  title and cascades every descendant slug - the gap a backend rename
  leaves open. Used to fix the "Engagament" page (#465): title, own
  slug and five child slugs in one run, verified live (zero occurrences
  left in the JSON)
- SubsolutionWorkbookImporter::norm() tolerates the engagament spelling:
  the 39 delivered workbook metas carry the old page title, re-imports
  keep matching (verified)
- typo3/cms-redirects installed - it had NEVER been installed, so every
  "redirect follows" of the 10-23 renames was wishful thinking and all
  old URLs answered 404. Backend slug changes now auto-create redirects
- EXT:redirects' auto-creation does not fire for CLI DataHandler runs,
  so vitec:rename-page, vitec:normalize-slugs and
  vitec:align-market-pages now queue their 301 sys_redirect rows
  themselves in the same DataHandler run
- new one-off vitec:backfill-redirects: the 28 paths vacated on
  2026-10-23/26, reconstructed from the command protocols, guarded
  against existing redirects and live slugs; applied and verified.
  Note the headless semantics: a redirect arrives as the JSON envelope
  {"redirectUrl": ..., "statusCode": 301} with HTTP 200 - the front end
  must act on redirectUrl (briefing updated)

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

composer.lock

@@ -10425,10 +10425,10 @@
     },
     "prefer-stable": false,
     "prefer-lowest": false,
-    "platform": [],
-    "platform-dev": [],
+    "platform": {},
+    "platform-dev": {},
     "platform-overrides": {
         "php": "8.4.0"
     },
-    "plugin-api-version": "2.3.0"
+    "plugin-api-version": "2.9.0"
 }