Fix Dokploy Bad Gateway: panel-first compose and stable boot

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/entrypoint.sh

@@ -1,6 +1,21 @@
 #!/bin/sh
 set -e
 
+echo "==> VpnPanel starting"
+
+# Always build DATABASE_URL from POSTGRES_* (Dokploy-friendly)
+export DATABASE_URL="$(
+  python - <<'PY'
+import os
+from urllib.parse import quote_plus
+
+user = os.environ.get("POSTGRES_USER", "vpn")
+password = os.environ.get("POSTGRES_PASSWORD", "vpn")
+db = os.environ.get("POSTGRES_DB", "vpn_panel")
+print(f"postgresql+asyncpg://{quote_plus(user)}:{quote_plus(password)}@postgres:5432/{db}")
+PY
+)"
+
 echo "Waiting for database..."
 python - <<'PY'
 import asyncio
@@ -11,7 +26,7 @@ from sqlalchemy import text
 from sqlalchemy.ext.asyncio import create_async_engine
 
 
-async def wait_db(retries: int = 40) -> None:
+async def wait_db(retries: int = 60) -> None:
     url = os.environ["DATABASE_URL"]
     engine = create_async_engine(url)
     for i in range(retries):
@@ -25,6 +40,7 @@ async def wait_db(retries: int = 40) -> None:
             print(f"DB not ready ({i + 1}/{retries}): {exc}")
             await asyncio.sleep(1)
     await engine.dispose()
+    print("ERROR: database did not become ready", file=sys.stderr)
     sys.exit(1)
 
 
@@ -37,5 +53,5 @@ alembic upgrade head
 echo "Bootstrapping admin..."
 python -m app.bootstrap
 
-echo "Starting application..."
+echo "Starting uvicorn..."
 exec "$@"