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/Makefile

@@ -0,0 +1,12 @@
+TAILWIND := ./bin/tailwindcss
+
+bin/tailwindcss:
+	@mkdir -p bin
+	curl -sLo bin/tailwindcss https://github.com/tailwindlabs/tailwindcss/releases/latest/download/tailwindcss-linux-x64
+	chmod +x bin/tailwindcss
+
+css-build: bin/tailwindcss
+	$(TAILWIND) -i src/beanflows/static/css/input.css -o src/beanflows/static/css/output.css --minify
+
+css-watch: bin/tailwindcss
+	$(TAILWIND) -i src/beanflows/static/css/input.css -o src/beanflows/static/css/output.css --watch