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/.copier-answers.yml

@@ -1,6 +1,6 @@
 # Changes here will be overwritten by Copier; NEVER EDIT MANUALLY
 _commit: v0.3.0
-_src_path: /home/Deeman/Projects/quart_saas_boilerplate
+_src_path: git@gitlab.com:deemanone/materia_saas_boilerplate.master.git
 author_email: hendrik@beanflows.coffee
 author_name: Hendrik Deeman
 base_url: https://beanflows.coffee