fix: preserve portable rollback mount identity

tools/thothctl/internal/pi/state.go

@@ -42,12 +42,13 @@ type Image struct {
 
 // Mount is the complete persistence identity relevant to safe core recreation.
 type Mount struct {
-	Type         string `json:"type"`
-	Name         string `json:"name,omitempty"`
-	SourceSHA256 string `json:"source_sha256"`
-	Destination  string `json:"destination"`
-	RW           bool   `json:"rw"`
-	Options      string `json:"options,omitempty"`
+	Type          string   `json:"type"`
+	Name          string   `json:"name,omitempty"`
+	SourceSHA256  string   `json:"source_sha256"`
+	SourceAliases []string `json:"-"`
+	Destination   string   `json:"destination"`
+	RW            bool     `json:"rw"`
+	Options       string   `json:"options,omitempty"`
 }
 
 // Target records the immutable input selected by the operator. Source is either build or a
@@ -136,17 +137,27 @@ func writeFileDurably(path, prefix string, contents []byte) error {
 }
 
 func mountSourceHash(source string) string {
-	source = filepath.Clean(source)
-	for _, dockerDesktopPrefix := range []string{"/host_mnt/private/var/", "/host_mnt/Users/"} {
-		if strings.HasPrefix(source, dockerDesktopPrefix) {
-			source = strings.TrimPrefix(source, "/host_mnt")
-			break
-		}
-	}
 	sum := sha256.Sum256([]byte(source))
 	return fmt.Sprintf("%x", sum[:])
 }
 
+func mountSourceAliases(mountType, source, goos string) []string {
+	if mountType != "bind" || goos != "darwin" {
+		return nil
+	}
+	source = filepath.Clean(source)
+	var alias string
+	switch {
+	case strings.HasPrefix(source, "/host_mnt/private/var/"), strings.HasPrefix(source, "/host_mnt/Users/"):
+		alias = strings.TrimPrefix(source, "/host_mnt")
+	case strings.HasPrefix(source, "/private/var/"), strings.HasPrefix(source, "/Users/"):
+		alias = "/host_mnt" + source
+	default:
+		return nil
+	}
+	return []string{mountSourceHash(alias)}
+}
+
 func mountFingerprint(mounts []Mount) string {
 	values := make([]string, len(mounts))
 	for i, mount := range mounts {