fix(build): add production API URLs to Docker build

Dockerfile now passes --dart-define flags for CORE_API_URL and
TATLOCK_API_URL pointing to schweitz.net domains. This enables
requiresAuth=true, fixing auth being completely skipped in production.

Also added service port reference table to AGENTS.md.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

AGENTS.md

@@ -47,7 +47,7 @@ When changes are ready for deployment:
 5. **CI/CD triggers automatically**:
    - Gitea CI builds Docker image on new tag
    - Watchtower pulls and deploys to production
-   - Verify deployment: `curl http://192.168.86.149:8000/health`
+   - Verify deployment: `curl http://192.168.86.149:8083/health`
 
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