Make PromptKit profile handling safer and more consistent

internal/framework/llm/promptkit_profile_fingerprint.go

@@ -27,18 +27,21 @@ func promptKitProfileFingerprint(profileDir, profileFile, fallbackProfileDigest
 
 	switch {
 	case strings.TrimSpace(profileFile) != "":
-		data, err := os.ReadFile(strings.TrimSpace(profileFile))
+		cleanProfileFile := strings.TrimSpace(profileFile)
+		data, err := os.ReadFile(cleanProfileFile)
 		if err != nil {
 			return CheckpointFingerprint{}, fmt.Errorf("read PromptKit profile file for checkpoint identity")
 		}
+		writeFingerprintPart(hasher, []byte(filepath.ToSlash(filepath.Base(cleanProfileFile))))
 		writeFingerprintPart(hasher, data)
 	case strings.TrimSpace(profileDir) != "":
-		digests, err := promptKitProfileFileDigests(strings.TrimSpace(profileDir))
+		files, err := promptKitProfileFiles(strings.TrimSpace(profileDir))
 		if err != nil {
 			return CheckpointFingerprint{}, err
 		}
-		for _, digest := range digests {
-			writeFingerprintPart(hasher, digest)
+		for _, file := range files {
+			writeFingerprintPart(hasher, []byte(file.path))
+			writeFingerprintPart(hasher, file.digest)
 		}
 	}
 
@@ -58,8 +61,13 @@ func promptKitLocalBackendFingerprint(endpoint string) CheckpointFingerprint {
 	}
 }
 
-func promptKitProfileFileDigests(root string) ([][]byte, error) {
-	var digests [][]byte
+type promptKitProfileFile struct {
+	path   string
+	digest []byte
+}
+
+func promptKitProfileFiles(root string) ([]promptKitProfileFile, error) {
+	var files []promptKitProfileFile
 	err := filepath.WalkDir(root, func(name string, entry fs.DirEntry, walkErr error) error {
 		if walkErr != nil {
 			return walkErr
@@ -75,17 +83,24 @@ func promptKitProfileFileDigests(root string) ([][]byte, error) {
 		if err != nil {
 			return err
 		}
+		relativePath, err := filepath.Rel(root, name)
+		if err != nil {
+			return err
+		}
 		sum := sha256.Sum256(data)
-		digests = append(digests, append([]byte(nil), sum[:]...))
+		files = append(files, promptKitProfileFile{
+			path:   filepath.ToSlash(relativePath),
+			digest: append([]byte(nil), sum[:]...),
+		})
 		return nil
 	})
 	if err != nil {
 		return nil, fmt.Errorf("read PromptKit profile directory for checkpoint identity")
 	}
-	sort.Slice(digests, func(i, j int) bool {
-		return string(digests[i]) < string(digests[j])
+	sort.Slice(files, func(i, j int) bool {
+		return files[i].path < files[j].path
 	})
-	return digests, nil
+	return files, nil
 }
 
 func writeFingerprintPart(hasher interface{ Write([]byte) (int, error) }, value []byte) {