feat: execute workflow bridge nodes in graph runtime

backend/app/domains/rendering/workflow_router.py

@@ -228,12 +228,9 @@ async def dispatch_workflow_endpoint(
     the caller can track progress.
     """
     from pydantic import ValidationError as _ValidationError
-    from app.domains.rendering.workflow_executor import (
-        dispatch_prepared_workflow,
-        prepare_workflow_context,
-    )
+    from app.domains.rendering.workflow_executor import prepare_workflow_context
+    from app.domains.rendering.workflow_graph_runtime import execute_graph_workflow
     from app.domains.rendering.workflow_run_service import (
-        apply_graph_dispatch_result,
         create_workflow_run,
         mark_workflow_run_failed,
     )
@@ -269,7 +266,9 @@ async def dispatch_workflow_endpoint(
     await db.commit()
 
     try:
-        dispatch_result = dispatch_prepared_workflow(workflow_context)
+        dispatch_result = await db.run_sync(
+            lambda sync_session: execute_graph_workflow(sync_session, workflow_context)
+        )
     except Exception as exc:
         failed_result = await db.execute(
             select(WorkflowRun)
@@ -280,14 +279,6 @@ async def dispatch_workflow_endpoint(
         mark_workflow_run_failed(failed_run, str(exc))
         await db.commit()
         raise
-
-    run_result = await db.execute(
-        select(WorkflowRun)
-        .where(WorkflowRun.id == run_id)
-        .options(selectinload(WorkflowRun.node_results))
-    )
-    run = run_result.scalar_one()
-    apply_graph_dispatch_result(run, workflow_context, dispatch_result)
     await db.commit()
 
     refreshed_result = await db.execute(