fix: close PI-090 review findings

electron/coding-runtime/pi/extension-host.ts

@@ -88,7 +88,20 @@ interface ChangeRefreshBridgeRequest {
   resourceId: string;
 }
 
-type BridgeRequest = LeaseBridgeRequest | SubagentBridgeRequest | ProductToolBridgeRequest | ChangeRefreshBridgeRequest;
+interface ChangeTouchedBridgeRequest {
+  action: 'changes.touched';
+  conversationId: string;
+  workerGeneration: number;
+  runId: string;
+  resourceId: string;
+  paths: string[];
+}
+
+type BridgeRequest = LeaseBridgeRequest
+  | SubagentBridgeRequest
+  | ProductToolBridgeRequest
+  | ChangeRefreshBridgeRequest
+  | ChangeTouchedBridgeRequest;
 
 export interface PiExtensionSubagentBridge {
   scheduler: PiSubagentScheduler;
@@ -111,6 +124,12 @@ function bridgeRequest(value: unknown): value is BridgeRequest {
     return typeof value.toolName === 'string' && 'input' in value;
   }
   if (value.action === 'changes.bash') return true;
+  if (value.action === 'changes.touched') {
+    return Array.isArray(value.paths)
+      && value.paths.length > 0
+      && value.paths.length <= 200
+      && value.paths.every((filePath) => typeof filePath === 'string');
+  }
   return (value.action === 'lease.acquire' || value.action === 'lease.release')
     && (value.leaseId === undefined || typeof value.leaseId === 'string');
 }
@@ -304,6 +323,19 @@ export class PiManagedExtensionHost {
         this.respond(response, 200, { marked: true });
         return;
       }
+      if (value.action === 'changes.touched') {
+        if (!this.productTools) {
+          this.respond(response, 503, { error: 'Conversation change tracker is unavailable' });
+          return;
+        }
+        await this.productTools.recordTouchedPaths(
+          record.conversationId,
+          value.runId,
+          value.paths,
+        );
+        this.respond(response, 200, { recorded: true });
+        return;
+      }
       if (value.action === 'product.invoke') {
         if (record.role !== 'parent') {
           this.respond(response, 403, { error: 'Child workers cannot invoke parent product tools' });