Add prowlarr stack compose file

Convert prowlarr from inline UI config to git repo-based configuration.

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

stacks/prowlarr.compose.yml

@@ -0,0 +1,14 @@
+services:
+  prowlarr:
+    container_name: prowlarr
+    image: ghcr.io/hotio/prowlarr
+    ports:
+      - "9696:9696"
+    environment:
+      - PUID=1000
+      - PGID=1000
+      - UMASK=002
+      - TZ=Etc/UTC
+    volumes:
+      - /volume2/data:/data:rw
+      - /volume2/docker/prowlarr:/config:rw