fix: Add env_file directive to Docker Compose configurations

- Add env_file directive to docker-compose.astro.yml
- Add env_file directive to docker-compose.override.yml
- Ensures Docker Compose loads .env file properly
- Fixes environment variable substitution (${PUBLIC_SUPABASE_URL}, etc.)

Without this, environment variables were undefined in containers
causing connection failures to Supabase and other services.

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

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

docker-compose.astro.yml

@@ -12,6 +12,8 @@ services:
     labels:
       - "com.blackcanyon.role=astro-app"
       - "maintainer=tyler@crispygoat.com"
+    env_file:
+      - .env
     environment:
       - NODE_ENV=production
       - HOST=0.0.0.0