fix: support labeled action for pull_request events in track_progress (#1586)

Adds "labeled" to the valid pull_request actions for track_progress,
mirroring the existing support for issue events. Previously, adding
a label to a PR (e.g. to trigger a label-driven Claude review) would
fail validation even though the same pattern works for issues.

Fixes #1585

action.yml

@@ -134,7 +134,7 @@ inputs:
     required: false
     default: "claude[bot]"
   track_progress:
-    description: "Force tag mode with tracking comments for pull_request and issue events. Only applicable to pull_request (opened, synchronize, ready_for_review, reopened) and issue (opened, edited, labeled, assigned) events."
+    description: "Force tag mode with tracking comments for pull_request and issue events. Only applicable to pull_request (opened, synchronize, ready_for_review, reopened, labeled) and issue (opened, edited, labeled, assigned) events."
     required: false
     default: "false"
   include_fix_links:

src/modes/detector.ts

@@ -103,6 +103,7 @@ function validateTrackProgressEvent(context: GitHubContext): void {
       "synchronize",
       "ready_for_review",
       "reopened",
+      "labeled",
     ];
     if (!validActions.includes(context.eventAction)) {
       throw new Error(

test/modes/detector.test.ts

@@ -76,6 +76,20 @@ describe("detectMode with enhanced routing", () => {
       expect(detectMode(context)).toBe("agent");
     });
 
+    it("should use tag mode when track_progress is true for pull_request.labeled", () => {
+      const context: GitHubContext = {
+        ...baseContext,
+        eventName: "pull_request",
+        eventAction: "labeled",
+        payload: { pull_request: { number: 1 } } as any,
+        entityNumber: 1,
+        isPR: true,
+        inputs: { ...baseContext.inputs, trackProgress: true },
+      };
+
+      expect(detectMode(context)).toBe("tag");
+    });
+
     it("should throw error when track_progress is used with unsupported PR action", () => {
       const context: GitHubContext = {
         ...baseContext,