Automate Gitea init, NocoDB auto sign-in, and fix prod compose

- Add scripts/gitea-init.sh: runs migrations + creates admin user on
  first boot, replacing the manual installation wizard
- Set GITEA__security__INSTALL_LOCK=true in both compose files
- Add NocoDB auth bridge (nginx) + /api/services/nocodb-auth proxy
  endpoint so the admin iframe auto-authenticates
- Update NocoDBPage.tsx to fetch token and use auth bridge flow
- Fix docker-compose.prod.yml missing Gitea env vars for API container
  (GITEA_URL, GITEA_API_TOKEN, GITEA_ADMIN_PASSWORD, etc.)
- Pass NC_ADMIN_EMAIL/PASSWORD to API for NocoDB auth proxy
- Increase Gitea auto-setup retries from 3 to 6 with admin auth check
- Update config.sh non-interactive mode to set GITEA_ADMIN_USER
- Include gitea-init.sh in release tarball (build-release.sh)

Bunker Admin

.env.example

@@ -222,6 +222,8 @@ GITEA_URL=http://gitea-changemaker:3000
 GITEA_PORT=3030
 GITEA_WEB_PORT=3030
 GITEA_SSH_PORT=2222
+# Admin user (auto-created on first boot by gitea-init.sh)
+GITEA_ADMIN_USER=admin
 GITEA_DB_TYPE=mysql
 GITEA_DB_HOST=gitea-db:3306
 GITEA_DB_NAME=gitea