feat: reintegrate MCP server with proper session manager lifecycle, nginx /mcp proxy, docker.sock mount

backend/app/mcp_server.py

@@ -122,20 +122,7 @@ _STATIC_COMPONENTS = [
 # streamable_http_path="/" so that when mounted at /mcp the endpoint is /mcp/
 # stateless_http=True: each request is independent (no session management)
 # Disable DNS rebinding protection for Docker deployment
-try:
-    from mcp.server.fastmcp.settings import TransportSecuritySettings
-    _ts = TransportSecuritySettings(enable_dns_rebinding_protection=False)
-except Exception:
-    _ts = None
-
-_mcp_kwargs: dict[str, Any] = {
-    "streamable_http_path": "/",
-    "stateless_http": True,
-}
-if _ts is not None:
-    _mcp_kwargs["transport_security"] = _ts
-
-mcp = FastMCP("hms-cms", **_mcp_kwargs)
+mcp = FastMCP("hms-cms", streamable_http_path="/", stateless_http=True)
 
 # ---------------------------------------------------------------------------#
 # Bearer token authentication wrapper