feat(admin): standalone Projects page + per-project asset manager

- content-svc: GET /v1/projects (browse/search all projects across containers,
  paginated, admin) returning template name/slug + AE status; project_assets
  table (mig 23) + entity; GET/POST/DELETE /v1/projects/{id}/assets
- /admin/projects: searchable, paginated list of every renderable project with
  thumbnail, template, aspect/resolution, AE-file + publish status
- ProjectAssets component: list/upload/delete named footage/image/audio/font
  files per project (reused in the projects page; AE file upload alongside)
- nav + fa/en "Projects" label

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

messages/en.json

@@ -333,7 +333,8 @@
       "homeEvents": "Home Events",
       "comments": "Comments",
       "routes": "Internal Routes",
-      "integrations": "Integrations"
+      "integrations": "Integrations",
+      "projects": "Projects"
     },
     "appAdminNodesPage": {
       "title": "Render Nodes",