fix(sync): stop sync loop and apply remote state once

- Await restorePersistedTunnels in applySyncedState so applyingSync stays
  true for the full restore. Prevents saveState() during tunnel startup
  from pushing back to autopass and causing a feedback loop.
- Debounce onRemoteUpdate (600ms) so bursts of autopass 'update' events
  trigger a single apply.
- Skip apply when remote state matches current state (canonical fingerprint)
  to avoid redundant restarts and re-pushes.
- Clear remoteUpdateDebounceTimer in cleanup().

native-host/managers/sync-manager.js

@@ -12,6 +12,7 @@ const STATE_KEY = 'holesail-state';
 const IDENTITY_FILENAME = 'autopass-identity.json';
 const STATE_FILENAME = 'state.json';
 const AUTOPASS_DIRNAME = 'autopass';
+const REMOTE_UPDATE_DEBOUNCE_MS = 600;
 
 let storageDir = null;
 let holesailManager = null;
@@ -27,6 +28,7 @@ let initPromise = null;
 let applyingSync = false;
 let weJustPushed = false;
 let lastSyncedAt = null;
+let remoteUpdateDebounceTimer = null;
 
 function setStoragePath(dir) {
   storageDir = dir;
@@ -141,15 +143,45 @@ async function ensureInitialized() {
   await initPromise;
 }
 
-async function onRemoteUpdate() {
+/**
+ * Canonical string form of state for comparison (sorted keys at every level).
+ */
+function stateFingerprint(obj) {
+  if (obj === null || typeof obj !== 'object') return JSON.stringify(obj);
+  if (Array.isArray(obj)) return '[' + obj.map(stateFingerprint).join(',') + ']';
+  const keys = Object.keys(obj).sort();
+  const parts = keys.map((k) => JSON.stringify(k) + ':' + stateFingerprint(obj[k]));
+  return '{' + parts.join(',') + '}';
+}
+
+function onRemoteUpdate() {
   if (weJustPushed) return;
   if (!pass || !holesailManager) return;
+  if (remoteUpdateDebounceTimer) clearTimeout(remoteUpdateDebounceTimer);
+  remoteUpdateDebounceTimer = setTimeout(() => {
+    remoteUpdateDebounceTimer = null;
+    applyRemoteUpdate().catch((e) => {
+      if (process.stderr) process.stderr.write('[sync-manager] applyRemoteUpdate failed: ' + e.message + '\n');
+    });
+  }, REMOTE_UPDATE_DEBOUNCE_MS);
+}
+
+async function applyRemoteUpdate() {
+  if (weJustPushed || !pass || !holesailManager) return;
   try {
     const entry = await pass.get(STATE_KEY);
     if (!entry || entry.value == null) return;
     const str = typeof entry.value === 'string' ? entry.value : (entry.value && entry.value.toString ? entry.value.toString() : '');
     if (!str) return;
     const snapshot = JSON.parse(str);
+    const statePath = getStateFilePath();
+    if (statePath && fs.existsSync(statePath)) {
+      try {
+        const currentRaw = fs.readFileSync(statePath, 'utf8');
+        const current = JSON.parse(currentRaw);
+        if (stateFingerprint(current) === stateFingerprint(snapshot)) return;
+      } catch (_) {}
+    }
     await applySyncedState(snapshot);
     lastSyncedAt = Date.now();
     if (emitEvent) emitEvent('syncApplied', {});
@@ -160,7 +192,8 @@ async function onRemoteUpdate() {
 
 /**
  * Write state snapshot to state.json and run the same restore flow as backup restore.
- * Does not touch certs.
+ * Does not touch certs. Keeps applyingSync true until all tunnels are restored so
+ * saveState() calls during restore do not push back to autopass and cause a loop.
  */
 async function applySyncedState(snapshot) {
   if (!holesailManager || !setTunnelsRestoredPromise || !restorePersistedTunnels) return;
@@ -174,9 +207,11 @@ async function applySyncedState(snapshot) {
     fs.writeFileSync(statePath, json, 'utf8');
     await holesailManager.cleanup().catch(() => {});
     const restored = holesailManager.restorePersistedState();
-    setTunnelsRestoredPromise(
-      restorePersistedTunnels(holesailManager, restored).catch((e) => log('Post-sync tunnel restore failed:', e.message))
+    const restorePromise = restorePersistedTunnels(holesailManager, restored).catch((e) =>
+      log('Post-sync tunnel restore failed:', e.message)
     );
+    setTunnelsRestoredPromise(restorePromise);
+    await restorePromise;
   } finally {
     applyingSync = false;
   }
@@ -287,6 +322,10 @@ async function cleanup() {
   initPromise = null;
   weJustPushed = false;
   applyingSync = false;
+  if (remoteUpdateDebounceTimer) {
+    clearTimeout(remoteUpdateDebounceTimer);
+    remoteUpdateDebounceTimer = null;
+  }
   if (pass && pass.off) pass.off('update', onRemoteUpdate);
   await closePass();
 }