feat: add Tandoor recipe manager to infrastructure

Added Tandoor Recipes as a comprehensive recipe management solution:

**Tandoor Stack** (tandoor.pivoine.art):
- Modern recipe manager with smart scaling and collaboration
- PostgreSQL backend for recipe persistence
- Email notifications via IONOS SMTP
- Static and media file storage in dedicated volumes
- User signups disabled (admin-only access)

**Features:**
- Smart recipe scaling (auto-adjust ingredients for servings)
- Spaces for collaboration (family/roommate recipe sharing)
- Meal planning and shopping lists
- Recipe import from URLs
- Mobile app support (Kitshn app)
- Nutritional information and pricing

**Infrastructure updates:**
- Added tandoor database to PostgreSQL init script
- Added environment variables to arty.yml
- Updated compose.yaml include list
- Added Tandoor volumes (staticfiles, mediafiles) to Restic backup
- Configured email notifications for invitations and notifications

**Tech stack:**
- Django/Python backend
- Vue.js frontend
- PostgreSQL database (shared core instance)
- Gunicorn WSGI server

Tandoor provides superior UX compared to Mealie with better recipe
scaling, collaboration features, and mobile app experience.

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

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

core/postgres/init/01-init-databases.sh

@@ -33,6 +33,10 @@ psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" <<-E
     SELECT 'CREATE DATABASE mattermost'
     WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mattermost')\gexec
 
+    -- Tandoor recipe manager database
+    SELECT 'CREATE DATABASE tandoor'
+    WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'tandoor')\gexec
+
     -- Grant privileges to all databases
     GRANT ALL PRIVILEGES ON DATABASE directus TO $POSTGRES_USER;
     GRANT ALL PRIVILEGES ON DATABASE umami TO $POSTGRES_USER;
@@ -40,11 +44,12 @@ psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" <<-E
     GRANT ALL PRIVILEGES ON DATABASE linkwarden TO $POSTGRES_USER;
     GRANT ALL PRIVILEGES ON DATABASE joplin TO $POSTGRES_USER;
     GRANT ALL PRIVILEGES ON DATABASE mattermost TO $POSTGRES_USER;
+    GRANT ALL PRIVILEGES ON DATABASE tandoor TO $POSTGRES_USER;
 
     -- Log success
     SELECT 'Compose databases initialized:' AS status;
     SELECT datname FROM pg_database
-    WHERE datname IN ('directus', 'umami', 'n8n', 'linkwarden', 'joplin', 'mattermost')
+    WHERE datname IN ('directus', 'umami', 'n8n', 'linkwarden', 'joplin', 'mattermost', 'tandoor')
     ORDER BY datname;
 EOSQL
 
@@ -59,4 +64,5 @@ echo "  • n8n          - Workflow automation database"
 echo "  • linkwarden   - Bookmark manager database"
 echo "  • joplin       - Note-taking server database"
 echo "  • mattermost   - Chat platform database"
+echo "  • tandoor      - Recipe manager database"
 echo ""