fix(auth): ensure absolute paths for auth file handling

internal/api/handlers/management/auth_files.go

@@ -739,10 +739,25 @@ func (h *Handler) authIDForPath(path string) string {
 	if path == "" {
 		return ""
 	}
+	path = filepath.Clean(path)
+	if !filepath.IsAbs(path) {
+		if abs, errAbs := filepath.Abs(path); errAbs == nil {
+			path = abs
+		}
+	}
 	id := path
 	if h != nil && h.cfg != nil {
 		authDir := strings.TrimSpace(h.cfg.AuthDir)
+		if resolvedAuthDir, errResolve := util.ResolveAuthDir(authDir); errResolve == nil && resolvedAuthDir != "" {
+			authDir = resolvedAuthDir
+		}
 		if authDir != "" {
+			authDir = filepath.Clean(authDir)
+			if !filepath.IsAbs(authDir) {
+				if abs, errAbs := filepath.Abs(authDir); errAbs == nil {
+					authDir = abs
+				}
+			}
 			if rel, errRel := filepath.Rel(authDir, path); errRel == nil && rel != "" {
 				id = rel
 			}