fix(gsd): repair DB-only milestone unpark state

src/resources/extensions/gsd/milestone-actions.ts

@@ -20,7 +20,7 @@ import {
 } from "./paths.js";
 import { invalidateAllCaches } from "./cache.js";
 import { loadQueueOrder, saveQueueOrder } from "./queue-order.js";
-import { isDbAvailable, updateMilestoneStatus } from "./gsd-db.js";
+import { getMilestone, isDbAvailable, updateMilestoneStatus } from "./gsd-db.js";
 import { logWarning } from "./workflow-logger.js";
 
 // ─── Park ──────────────────────────────────────────────────────────────────
@@ -77,9 +77,16 @@ export function unparkMilestone(basePath: string, milestoneId: string): boolean
   if (!mDir || !existsSync(mDir)) return false;
 
   const parkedPath = join(mDir, buildMilestoneFileName(milestoneId, "PARKED"));
-  if (!existsSync(parkedPath)) return false; // not parked
+  const hadParkedFile = existsSync(parkedPath);
+  const dbThinksParked = isDbAvailable() && getMilestone(milestoneId)?.status === "parked";
 
-  unlinkSync(parkedPath);
+  // Recover the reverse desync too: DB can still say "parked" even when the
+  // PARKED marker was lost on disk, and /gsd unpark should repair that state.
+  if (!hadParkedFile && !dbThinksParked) return false;
+
+  if (hadParkedFile) {
+    unlinkSync(parkedPath);
+  }
   // Sync DB status so deriveStateFromDb picks up the unparked milestone (#2694)
   if (isDbAvailable()) {
     try {

src/resources/extensions/gsd/tests/park-db-sync.test.ts

@@ -69,6 +69,24 @@ test("unparkMilestone updates DB status to 'active' (#2694)", () => {
   }
 });
 
+test("unparkMilestone repairs parked DB state when PARKED.md is missing (#3707)", () => {
+  const base = createBase();
+  try {
+    openDatabase(":memory:");
+    insertMilestone({ id: "M001", title: "Test", status: "parked" });
+
+    const unparked = unparkMilestone(base, "M001");
+
+    assert.ok(unparked, "unparkMilestone should recover DB-only parked state");
+    assert.equal(getMilestone("M001")!.status, "active", "DB status should be repaired to active");
+
+    closeDatabase();
+  } finally {
+    closeDatabase();
+    rmSync(base, { recursive: true, force: true });
+  }
+});
+
 test("park/unpark are safe when DB is not available (#2694 guard)", () => {
   const base = createBase();
   try {