Make docker-entrypoint pass through command args

The node:24 base image sets ENTRYPOINT ["docker-entrypoint.sh"]. We
override that script but the ENTRYPOINT still runs on every start, so
compose's `command:` was being handed to our script as args (and
silently ignored — we always exec'd `node dist/main.js`). That made the
`sleep infinity` override useless: the crash-looping app kept running.

Fix by execing "$@" when args are present so compose overrides work,
and set CMD to ["node","dist/main.js"] so normal (no-override) starts
still boot the app.

docker-entrypoint.sh

@@ -16,4 +16,8 @@ else
   echo "[entrypoint] pi-claude-code-provider already installed"
 fi
 
-exec node dist/main.js
+if [ $# -gt 0 ]; then
+  exec "$@"
+else
+  exec node dist/main.js
+fi