rework domain field

internal/api/admin_migrate.go

@@ -28,3 +28,29 @@ func (s *Server) handleMigrateDualRoots(w http.ResponseWriter, r *http.Request)
 		"fixed":   fixed,
 	})
 }
+
+// handleMigrateDomainScreen triggers the one-shot sweep that rewrites the
+// retired `domain=film|tv` values to `screen` and backfills `workForm` from
+// `contentKind` (METADATA_KEYS.md §14.17). See
+// storage.MigrateDomainScreen for why the vocabulary change is paid in the
+// data rather than with a read-side alias.
+//
+// Returns {fixed: N} — records changed, not records examined. Safe to call
+// repeatedly: a record already on the current vocabulary is skipped.
+func (s *Server) handleMigrateDomainScreen(w http.ResponseWriter, r *http.Request) {
+	if !s.storage.IsConnected() {
+		writeError(w, http.StatusServiceUnavailable, "storage not connected")
+		return
+	}
+
+	fixed, err := s.storage.MigrateDomainScreenWithTimeout()
+	if err != nil {
+		writeError(w, http.StatusInternalServerError, err.Error())
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"success": true,
+		"fixed":   fixed,
+	})
+}