feat: consolidate media services into unified media stack

- Combine Jellyfin, Filestash, and Koel into single media/ compose stack
- Remove standalone jelly/ and stash/ compose files
- Add Koel music streaming with PostgreSQL backend
- Update core PostgreSQL init script to create koel database
- Add media stack to root compose.yaml include
- Configure media services with subdomain routing (jellyfin.media, filestash.media, koel.media)

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

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

compose.yaml

@@ -7,12 +7,10 @@ include:
   - tandoor/compose.yaml
   - scrapy/compose.yaml
   - n8n/compose.yaml
-  - stash/compose.yaml
   - links/compose.yaml
   - vault/compose.yaml
   - joplin/compose.yaml
   - kit/compose.yaml
-  - jelly/compose.yaml
   - drop/compose.yaml
   - ai/compose.yaml
   - asciinema/compose.yaml
@@ -22,6 +20,7 @@ include:
   - sablier/compose.yaml
   - proxy/compose.yaml
   - watch/compose.yaml
+  - media/compose.yaml
 
 networks:
   compose_network: