fix(chat): drop root-level expectedArtifactDirs to satisfy chat.send schema

- Remove the unexpected property at the root of gateway task metadata.
  Keep the value nested in xworkmateTaskArtifactContract where the
  OpenClaw chat.send schema allows it (-32002: invalid chat.send params).
- Drop dead local vars and the unused asInt helper in OpenClaw task
  association parsing.
- Remove the obsolete 'sendChatMessage restarts before handling
  OpenClaw artifact guard results' test superseded by the new terminal
  artifact failure test.

lib/app/app_controller_desktop_runtime_helpers.dart

@@ -750,9 +750,6 @@ extension AppControllerDesktopRuntimeHelpers on AppController {
     );
     final artifacts = result.artifacts;
     if (artifacts.isEmpty) {
-      final requiredExts =
-          existingThread.openClawTaskAssociation?.requiredArtifactExtensions ??
-          const <String>[];
       final currentTaskArtifactRelativePaths =
           await _workspaceArtifactPathsModifiedSinceInternal(
               root,
@@ -782,7 +779,6 @@ extension AppControllerDesktopRuntimeHelpers on AppController {
     var wroteArtifact = false;
     var failedArtifact = false;
     var skippedArtifact = false;
-    var rejectedArtifact = false;
     final currentTaskArtifactPaths = <String>{};
     for (final artifact in artifacts) {
       final relativePath = _sanitizeArtifactRelativePathInternal(
@@ -813,7 +809,6 @@ extension AppControllerDesktopRuntimeHelpers on AppController {
         continue;
       }
       if (artifactSyncPolicy.rejects(artifact, relativePath, bytes)) {
-        rejectedArtifact = true;
         continue;
       }
       final target = await _nextArtifactTargetFileInternal(root, relativePath);

lib/app/app_controller_desktop_thread_actions.dart

@@ -771,10 +771,12 @@ extension AppControllerDesktopThreadActions on AppController {
         }
         if (aiGatewayPendingSessionKeysInternal.contains(sessionKey)) {
           final hasRequiredExts = current.requiredArtifactExtensions.isNotEmpty;
-          final hasEnoughArtifacts = !hasRequiredExts ||
+          final hasEnoughArtifacts =
+              !hasRequiredExts ||
               current.requiredArtifactExtensions.every((ext) {
                 return result.artifacts.any(
-                  (a) => a.relativePath.toLowerCase().endsWith(ext.toLowerCase()),
+                  (a) =>
+                      a.relativePath.toLowerCase().endsWith(ext.toLowerCase()),
                 );
               });
           if (!hasEnoughArtifacts && artifactRetries < 3) {
@@ -959,6 +961,7 @@ extension AppControllerDesktopThreadActions on AppController {
         'finalDeliverableDetection': 'remote-runtime',
         'requiresExportBeforeFinalResponse': true,
         'rejectTextOnlyFileClaims': true,
+        'expectedArtifactDirs': const <String>['artifacts/'],
         'currentTaskWorkspace': executionWorkspace.isNotEmpty
             ? executionWorkspace
             : (remoteHint.isNotEmpty ? remoteHint : localWorkspace),
@@ -1373,10 +1376,7 @@ extension AppControllerDesktopThreadActions on AppController {
     required Object error,
   }) async {
     clearAiGatewayStreamingTextInternal(sessionKey);
-    clearPendingToolCallsForGatewaySessionInternal(
-      sessionKey,
-      hasError: true,
-    );
+    clearPendingToolCallsForGatewaySessionInternal(sessionKey, hasError: true);
     final completedAtMs = DateTime.now().millisecondsSinceEpoch.toDouble();
     final recoveredArtifactPaths =
         await recoverGatewayFailureArtifactPathsInternal(sessionKey, error);

lib/runtime/runtime_models_runtime_payloads.dart

@@ -1013,16 +1013,6 @@ class OpenClawTaskAssociation {
     if (runId.isEmpty || artifactScope.isEmpty) {
       return null;
     }
-    int asInt(Object? raw) {
-      if (raw is int) {
-        return raw;
-      }
-      if (raw is num) {
-        return raw.toInt();
-      }
-      return int.tryParse(raw?.toString() ?? '') ?? 60;
-    }
-
     double asDouble(Object? raw) {
       if (raw is num) {
         return raw.toDouble();

test/runtime/assistant_execution_target_test.dart

@@ -1818,8 +1818,6 @@ void main() {
       },
     );
 
-    test(
-      'sendChatMessage restarts before handling OpenClaw artifact guard results',
     test(
       'sendChatMessage starts a new session after OpenClaw terminal artifact failure',
       () async {