feat: workspace 目录树服务端懒加载

- api.ts: listWorkspaceDirectories 支持 parent_path 查询; WorkspaceDirectory 增加 has_children; 同步 WorkspaceBoundApi 签名
- AuthContext: 绑定透传 parentPath
- scriptWorkspaceStore: 新增 expandedPaths/loadingChildrenPaths/loadedChildPaths, loadChildren/toggleExpanded, 局部刷新 createFolder/deleteDirectory
- WorkspaceTree: 移除 useState, 改为受控展开/加载状态
- ScriptExplorer: 从 store 读取并透传展开状态与 toggle

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

@@ -79,6 +79,9 @@ type State = {
   previewError: string | null;
 
   pythonEditorBuffers: Record<string, PythonEditorBuffer>;
+  expandedPaths: Set<string>;
+  loadingChildrenPaths: Set<string>;
+  loadedChildPaths: Set<string>;
 
   // actions
   setApiOnline: (online: boolean) => void;
@@ -103,6 +106,8 @@ type State = {
   createFolder: (name: string, parentPath: string) => Promise<void>;
   deleteScript: (script: ScriptItem) => Promise<void>;
   deleteDirectory: (path: string) => Promise<void>;
+  toggleExpanded: (path: string) => Promise<void>;
+  loadChildren: (parentPath: string) => Promise<void>;
   toggleScriptLock: (script: ScriptItem) => Promise<void>;
   openPublishDialog: (script: ScriptItem) => void;
   submitPublish: (releaseNote: string, visibility: Visibility) => Promise<void>;
@@ -166,6 +171,9 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
     previewError: null,
 
     pythonEditorBuffers: {},
+    expandedPaths: new Set<string>(),
+    loadingChildrenPaths: new Set<string>(),
+    loadedChildPaths: new Set<string>(),
 
     setApiOnline: (online) => set({ apiOnline: online }),
     setKeyword: (keyword) => set({ keyword }),
@@ -197,6 +205,9 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
         previewLoading: false,
         previewError: null,
         pythonEditorBuffers: {},
+        expandedPaths: new Set<string>(),
+        loadingChildrenPaths: new Set<string>(),
+        loadedChildPaths: new Set<string>(),
       });
     },
 
@@ -207,12 +218,15 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
       try {
         const [items, folderItems] = await Promise.all([
           api.listScripts(),
-          api.listWorkspaceDirectories(),
+          api.listWorkspaceDirectories(""),
         ]);
+        const nextLoaded = new Set(get().loadedChildPaths);
+        nextLoaded.add("");
         set({
           scripts: items,
           directories: folderItems,
           apiOnline: true,
+          loadedChildPaths: nextLoaded,
         });
         const validIds = new Set(items.map((item) => item.script_id));
         const currentSelected = get().selectedId;
@@ -236,6 +250,56 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
       }
     },
 
+    loadChildren: async (parentPath) => {
+      const api = requireApi();
+      if (get().loadedChildPaths.has(parentPath)) return;
+      const next = new Set(get().loadingChildrenPaths);
+      next.add(parentPath);
+      set({ loadingChildrenPaths: next });
+      try {
+        const children = await api.listWorkspaceDirectories(parentPath);
+        set((state) => {
+          const nextLoaded = new Set(state.loadedChildPaths);
+          nextLoaded.add(parentPath);
+          const trimmed = state.directories.filter(
+            (d) => d.parent_path !== parentPath,
+          );
+          return {
+            directories: [...trimmed, ...children],
+            loadedChildPaths: nextLoaded,
+            loadingChildrenPaths: new Set(
+              [...state.loadingChildrenPaths].filter((p) => p !== parentPath),
+            ),
+          };
+        });
+      } catch (error) {
+        set((state) => ({
+          loadingChildrenPaths: new Set(
+            [...state.loadingChildrenPaths].filter((p) => p !== parentPath),
+          ),
+        }));
+        pushToast(
+          "error",
+          error instanceof Error ? error.message : "目录加载失败",
+        );
+      }
+    },
+
+    toggleExpanded: async (path) => {
+      const state = get();
+      const isOpen = state.expandedPaths.has(path);
+      const next = new Set(state.expandedPaths);
+      if (isOpen) {
+        next.delete(path);
+      } else {
+        next.add(path);
+        if (!state.loadedChildPaths.has(path)) {
+          void get().loadChildren(path);
+        }
+      }
+      set({ expandedPaths: next });
+    },
+
     selectScript: (id) => {
       _selectedId = id;
       set({ selectedId: id });
@@ -712,7 +776,25 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
       ui.setFolderBusy(true);
       try {
         await api.createWorkspaceDirectory(trimmed, parentPath);
-        await get().load(true);
+        if (parentPath === "") {
+          await get().load(true);
+        } else {
+          set((state) => {
+            const nextLoaded = new Set(state.loadedChildPaths);
+            for (const p of state.loadedChildPaths) {
+              if (p.startsWith(`${parentPath}/`)) nextLoaded.delete(p);
+            }
+            nextLoaded.delete(parentPath);
+            return {
+              loadedChildPaths: nextLoaded,
+              directories: state.directories.filter(
+                (d) => !d.parent_path.startsWith(`${parentPath}/`),
+              ),
+              expandedPaths: new Set(state.expandedPaths),
+            };
+          });
+          await get().loadChildren(parentPath);
+        }
         ui.closeFolderDialog();
         pushToast("success", `${trimmed} 文件夹已创建`);
       } catch (error) {
@@ -779,6 +861,9 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
         await get().endEditing(false, false);
         if (_editSession?.script_id === activeScript.script_id) return;
       }
+      const parentPath = path.includes("/")
+        ? path.split("/").slice(0, -1).join("/")
+        : "";
       try {
         const result = await api.deleteWorkspaceDirectory(path);
         const selectedScript = get().scripts.find(
@@ -790,7 +875,28 @@ export const useScriptWorkspaceStore = create<State>((set, get) => {
         ) {
           get().selectScript(null);
         }
-        await get().load(true);
+        set((state) => {
+          const nextLoaded = new Set(state.loadedChildPaths);
+          const nextExpanded = new Set(state.expandedPaths);
+          for (const p of state.loadedChildPaths) {
+            if (p === path || p.startsWith(`${path}/`)) nextLoaded.delete(p);
+          }
+          for (const p of state.expandedPaths) {
+            if (p === path || p.startsWith(`${path}/`)) nextExpanded.delete(p);
+          }
+          return {
+            loadedChildPaths: nextLoaded,
+            expandedPaths: nextExpanded,
+            directories: state.directories.filter(
+              (d) => d.parent_path !== path && !d.parent_path.startsWith(`${path}/`),
+            ),
+          };
+        });
+        if (parentPath === "") {
+          await get().load(true);
+        } else {
+          await get().loadChildren(parentPath);
+        }
         pushToast(
           "success",
           `${path} 已删除（含 ${result.deleted_scripts} 个脚本）`,