fix: IsHiddenPath returns false for "." and "/" (current dir/root are not hidden)

path.Clean(".") returns "." which starts with a dot, causing IsHiddenPath
to incorrectly treat the current directory as hidden. Add explicit checks
for "." and "/" before the dot-prefix check.

Fixed in both mfer/scanner.go and internal/scanner/scanner.go.

internal/scanner/scanner.go

@@ -331,6 +331,9 @@ func (s *Scanner) ToManifest(ctx context.Context, w io.Writer, progress chan<- S
 // start with a dot (hidden files/directories).
 func pathIsHidden(p string) bool {
 	tp := path.Clean(p)
+	if tp == "." || tp == "/" {
+		return false
+	}
 	if strings.HasPrefix(tp, ".") {
 		return true
 	}