fix: use exec to properly handle container signals (#501)

- Replace direct command execution with exec to make app PID 1
- Ensures proper signal propagation in container
- Follows container best practices for process management

script/entrypoint.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
 printf "nameserver 127.0.0.11\nnameserver 8.8.4.4\nnameserver 223.5.5.5\n" > /etc/resolv.conf
-/dashboard/app
+exec /dashboard/app