add reading settings sync

internal/service/user_service.go

@@ -59,6 +59,20 @@ func (s *UserService) UpdateProfile(ctx context.Context, id string, name, avatar
 	return s.users.UpdateProfile(ctx, id, name, avatarURL, handle)
 }
 
+// GetReadingPrefs returns the user's reading prefs blob (opaque JSON).
+// Used by the frontend to hydrate ReadingSettings on sign-in so the
+// theme/palette/font choices roam across devices.
+func (s *UserService) GetReadingPrefs(ctx context.Context, id string) ([]byte, error) {
+	return s.users.GetReadingPrefs(ctx, id)
+}
+
+// UpdateReadingPrefs overwrites the user's reading prefs blob. The
+// handler re-marshals the decoded request before calling in here so we
+// know `prefsJSON` is well-formed by the time it hits the DB.
+func (s *UserService) UpdateReadingPrefs(ctx context.Context, id string, prefsJSON []byte) error {
+	return s.users.UpdateReadingPrefs(ctx, id, prefsJSON)
+}
+
 // normalizeHandle lowercases and strips anything that isn't [a-z0-9-]. Same
 // rules as slugForHandle in auth_service, but exposed here because the
 // profile-update path doesn't go through auth.