refactor(thothctl): share Pi lifecycle lock

tools/thothctl/internal/pi/state.go

@@ -180,13 +180,17 @@ type updateLock struct {
 	metadata string
 }
 
-var ErrLockHeld = errors.New("another Pi update or rollback is already in progress")
+var ErrLockHeld = errors.New("another Pi update, restart, or rollback is already in progress")
+
+func lifecycleLockPath(statePath string) string {
+	return filepath.Join(filepath.Dir(statePath), "pi-lifecycle.lock")
+}
 
 func acquireLock(statePath string) (*updateLock, error) {
 	if err := os.MkdirAll(filepath.Dir(statePath), 0o700); err != nil {
 		return nil, errors.New("could not create Pi update recovery directory")
 	}
-	path := statePath + ".lock"
+	path := lifecycleLockPath(statePath)
 	file := flock.New(path, flock.SetPermissions(0o600))
 	locked, err := file.TryLock()
 	if err != nil {