Fix club logo 404 in production and persist uploads

/media/* was only routed when DEBUG=True, so uploaded club logos
404d in production regardless of storage backend. Route it whenever
local-disk storage is in use instead, and give web a persistent
volume for MEDIA_ROOT so uploads survive a rebuild.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

compose.behind-proxy.yaml

@@ -19,6 +19,11 @@ services:
     env_file: .env.production
     ports:
       - "127.0.0.1:${WEB_PORT:-8001}:8000"
+    volumes:
+      # Uploaded club logos, while storage is local disk (see rosterchief/urls.py). Without
+      # this, a rebuild or recreate wipes MEDIA_ROOT even though the container itself keeps
+      # running fine in between.
+      - media_data:/app/media
     depends_on:
       db:
         condition: service_healthy
@@ -53,3 +58,4 @@ services:
 
 volumes:
   pgdata:
+  media_data: