refactor(web): 前端目录重构 — consoles/pages → layouts/features + shared

- consoles/admin/ → layouts/admin-layout/
- consoles/workbench/ → layouts/workbench-layout/ + features/chat/
- pages/ → features/ (dashboard, models, projects, not-found)
- components/ → shared/components/
- hooks/ → shared/hooks/
- utils/ → shared/utils/
- 更新所有 import 路径 (src/web/ + tests/web/)
- 更新开发文档 (README.md, frontend.md, architecture.md)

tests/web/utils/api.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, mock, test } from "bun:test";
 
-import { handleResponse, handleVoidResponse } from "../../../src/web/utils/api";
+import { handleResponse, handleVoidResponse } from "../../../src/web/shared/utils/api";
 
 function expectRejects(action: () => Promise<unknown>, message: string) {
   return action().then(