Fix web/ startup errors and sync with boilerplate

- Load .env via python-dotenv in core.py
- Skip analytics DB open if file doesn't exist
- Guard dashboard analytics calls when DB not available
- Namespace admin templates under admin/ to avoid blueprint conflicts
- Add dev-login routes for user and admin (DEBUG only)
- Update .copier-answers.yml src_path to GitLab remote

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/.env.example

@@ -1,7 +1,7 @@
 # App
 APP_NAME=BeanFlows
 SECRET_KEY=change-me-generate-a-real-secret
-BASE_URL=http://localhost:5000
+BASE_URL=http://localhost:5001
 DEBUG=true
 ADMIN_PASSWORD=admin