feat(scripts/data-resources): merge tree + add parent_path filter

- Backend: GET /api/v1/data-resources accepts parent_path; LIKE
  '{ws_id}/%/{escaped}/%' AND NOT LIKE '{ws_id}/%/{escaped}/%/%' on
  StorageObjects.object_key (workspace-wide, escapes _ and %, mirrors
  list_scripts parent_path semantics). 13 new tests in
  test_resources.py (helper unit / SQL compile / SQLite behavioral).
- Frontend: listResources gains parentPath arg, propagated through
  WorkspaceBoundApi + AuthContext binding. WorkspaceTreeGroup title
  count and ScriptExplorer header count now include dataResources.
  memberScriptGroups backfills data-only owners so users with only
  data resources still render a group. loadDataResources accepts an
  optional parentPath, default empty preserves prior behavior.

frontend/app/features/platform/WorkspaceTree.tsx

@@ -150,7 +150,7 @@ export function WorkspaceTreeGroup({
         <Icon name="chevron" size={14} />
         <Icon name="folder" size={17} />
         <span>{title}</span>
-        <em>{scripts.length}</em>
+        <em>{scripts.length + (dataResources ?? []).length}</em>
       </button>
       {open && (
         <div className="tree-group__items">

frontend/app/features/platform/state/scriptWorkspaceStore.ts

@@ -106,7 +106,7 @@ type State = {
  setKeyword: (keyword: string) => void;
  reset: () => void;
  load: (silent?: boolean) => Promise<void>;
-  loadDataResources: () => Promise<void>;
+  loadDataResources: (parentPath?: string) => Promise<void>;
  selectScript: (id: string | null) => void;
   openTab: (id: string) => void;
   closeTab: (id: string, event?: { stopPropagation: () => void }) => Promise<void>;
@@ -383,11 +383,11 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
       }
     },
 
-    loadDataResources: async () => {
+    loadDataResources: async (parentPath = "") => {
       const api = requireApi();
       set({ dataResourcesLoading: true });
       try {
-        const list = await api.listResources();
+        const list = await api.listResources(parentPath);
         set({ dataResources: Array.isArray(list) ? list : [] });
       } catch {
         set({ dataResources: [] });