chore(fs): linter complaints

lib/model/folder.go

@@ -1077,7 +1077,7 @@ func (f *folder) monitorWatch(ctx context.Context) {
 			f.setWatchError(err, next)
 			// This error was previously a panic and should never occur, so generate
 			// a warning, but don't do it repetitively.
-			var errOutside *fs.ErrWatchEventOutsideRoot
+			var errOutside *fs.WatchEventOutsideRootError
 			if errors.As(err, &errOutside) {
 				if !warnedOutside {
 					l.Warnln(err)

lib/model/folder_sendrecv.go

@@ -977,7 +977,7 @@ func (f *sendReceiveFolder) renameFile(cur, source, target protocol.FileInfo, db
 	}
 	switch stat, serr := f.mtimefs.Lstat(target.Name); {
 	case serr != nil:
-		var caseErr *fs.ErrCaseConflict
+		var caseErr *fs.CaseConflictError
 		switch {
 		case errors.As(serr, &caseErr):
 			if caseErr.Real != source.Name {
@@ -1149,7 +1149,7 @@ func (f *sendReceiveFolder) reuseBlocks(blocks []protocol.BlockInfo, reused []in
 	// reuse.
 	tempBlocks, err := scanner.HashFile(f.ctx, f.ID, f.mtimefs, tempName, file.BlockSize(), nil)
 	if err != nil {
-		var caseErr *fs.ErrCaseConflict
+		var caseErr *fs.CaseConflictError
 		if errors.As(err, &caseErr) {
 			if rerr := f.mtimefs.Rename(caseErr.Real, tempName); rerr == nil {
 				tempBlocks, err = scanner.HashFile(f.ctx, f.ID, f.mtimefs, tempName, file.BlockSize(), nil)

lib/model/folder_sendrecv_test.go

@@ -1014,7 +1014,7 @@ func TestPullCaseOnlyPerformFinish(t *testing.T) {
 	default:
 	}
 
-	var caseErr *fs.ErrCaseConflict
+	var caseErr *fs.CaseConflictError
 	if !errors.As(err, &caseErr) {
 		t.Error("Expected case conflict error, got", err)
 	}