fix(multitenant): register CapabilityServiceFactory in the backend

ExecutorService declares a hard dependency on CAPABILITY_SERVICE, but the
langflow backend's register_all_service_factories() registered
ExecutorServiceFactory without CapabilityServiceFactory. The service manager
could not resolve the dependency when building ExecutorService, so every flow
run failed with NoFactoryRegisteredError / "ExecutorService is not available".

lfx's own bootstrap (get_factories) auto-discovers the capability factory, so
lfx run/serve were unaffected; only the backend's hand-maintained factory list
had drifted. Add a regression test asserting the backend registers a factory
for every ExecutorService dependency.

Author: ogabrielluiz

src/backend/base/langflow/services/utils.py

@@ -487,6 +487,7 @@ def register_all_service_factories() -> None:
     from lfx.services.schema import ServiceType
 
     service_manager = get_service_manager()
+    from lfx.services.capability import factory as capability_factory
     from lfx.services.executor import factory as executor_factory
     from lfx.services.mcp_composer import factory as mcp_composer_factory
     from lfx.services.settings import factory as settings_factory
@@ -543,6 +544,9 @@ def register_all_service_factories() -> None:
     )
     service_manager.register_factory(authorization_factory.AuthorizationServiceFactory())
     service_manager.register_factory(mcp_composer_factory.MCPComposerServiceFactory())
+    # ExecutorService depends on CAPABILITY_SERVICE, so its factory must be
+    # registered too or the manager can't resolve the dependency.
+    service_manager.register_factory(capability_factory.CapabilityServiceFactory())
     service_manager.register_factory(executor_factory.ExecutorServiceFactory())
     service_manager.set_factory_registered()
 

src/backend/tests/unit/services/test_executor_capability_registration.py

@@ -0,0 +1,31 @@
+"""Regression test for the executor/capability service-factory wiring.
+
+``ExecutorService`` declares a hard dependency on ``CAPABILITY_SERVICE``. The
+langflow backend must register ``CapabilityServiceFactory`` alongside
+``ExecutorServiceFactory`` or the service manager cannot resolve the dependency
+when it builds ``ExecutorService`` -- which made every flow run 500 with
+``NoFactoryRegisteredError`` / "ExecutorService is not available".
+"""
+
+from __future__ import annotations
+
+from langflow.services.utils import register_all_service_factories
+from lfx.services.manager import get_service_manager
+from lfx.services.schema import ServiceType
+
+
+def test_executor_dependency_factories_are_registered():
+    register_all_service_factories()
+    service_manager = get_service_manager()
+
+    executor_factory = service_manager.factories.get(ServiceType.EXECUTOR_SERVICE.value)
+    assert executor_factory is not None, "ExecutorServiceFactory is not registered"
+
+    for dependency in executor_factory.dependencies:
+        assert dependency.value in service_manager.factories, (
+            f"ExecutorService depends on {dependency.value}, but no factory is registered for it; "
+            f"the service manager cannot build ExecutorService."
+        )
+
+    # The specific dependency that regressed.
+    assert ServiceType.CAPABILITY_SERVICE.value in service_manager.factories