fix(agent): restore active-task routing and active-mode validation observation

Keep correction follow-ups on Agent using session transcript and active task
context, and let Page Data validation reach Orchestrator when mode is active
instead of requiring shadowEngine.

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

services/orchestrator/shadow-observer.mjs

@@ -28,6 +28,19 @@ async function recordValidationWithRetry(engine, runId, observation) {
   }
 }
 
+export function resolveValidationEngineSelection(selection) {
+  if (selection.shadowEngine === WORKFLOW_ENGINE.LANGGRAPH) {
+    return selection;
+  }
+  if (
+    selection.engine === WORKFLOW_ENGINE.LANGGRAPH
+    && ['active', 'canary', 'shadow'].includes(String(selection.mode ?? ''))
+  ) {
+    return selection;
+  }
+  return null;
+}
+
 export function createWorkflowShadowObserver({
   configService,
   serviceToken = process.env.MEMIND_ORCHESTRATOR_SERVICE_TOKEN,
@@ -66,6 +79,34 @@ export function createWorkflowShadowObserver({
     };
   }
 
+  async function selectValidationEngine({
+    runId,
+    requestId,
+    userId,
+    workflowName,
+  }) {
+    const selection = await configService.selectEngine({
+      runId,
+      requestId,
+      userId,
+      workflowName,
+    });
+    if (!resolveValidationEngineSelection(selection)) {
+      return { selection, engine: null };
+    }
+    const state = await configService.getRuntimeState();
+    return {
+      selection,
+      engine: createRemoteWorkflowEngine({
+        id: WORKFLOW_ENGINE.LANGGRAPH,
+        baseUrl: state.config.serviceUrl,
+        serviceToken,
+        timeoutMs: state.config.requestTimeoutMs,
+        fetchImpl,
+      }),
+    };
+  }
+
   async function observeWorkflowRun({
     runId,
     requestId,
@@ -152,7 +193,7 @@ export function createWorkflowShadowObserver({
     workflowName = 'code-run-v1',
     observation,
   } = {}) {
-    const { selection, engine } = await selectShadowEngine({
+    const { selection, engine } = await selectValidationEngine({
       runId,
       requestId,
       userId,
@@ -187,5 +228,6 @@ export function createWorkflowShadowObserver({
 
 export const workflowShadowObserverInternals = {
   recordValidationWithRetry,
+  resolveValidationEngineSelection,
   safeError,
 };