refactor: move mcp adapter helper to wf_sources_mcp

tests/wf_mcp/test_compat_imports.py

@@ -245,3 +245,10 @@ def test_wf_mcp_broker_discovery_keeps_specs_adapter() -> None:
 
     assert broker_specs is not source_specs
     assert broker_specs.__name__ == "specs_from_discovered_tools"
+
+
+def test_wf_mcp_broker_service_adapter_shim_reexports_wf_sources_mcp_adapter_helper() -> None:
+    from wf_mcp.broker.service.adapters import require_adapter as compat_require_adapter
+    from wf_sources_mcp.adapters import require_adapter
+
+    assert compat_require_adapter is require_adapter