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)

src/web/layouts/workbench-layout/ProjectContextValue.ts

@@ -0,0 +1,5 @@
+import { createContext } from "react";
+
+import type { Project } from "../../../shared/api";
+
+export const ProjectContext = createContext<null | Project>(null);