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/components/chat/ReasoningPart.test.tsx

@@ -2,7 +2,7 @@ import { fireEvent, screen } from "@testing-library/react";
 import { describe, expect, test } from "bun:test";
 import { createElement } from "react";
 
-import { ReasoningPart } from "../../../../src/web/consoles/workbench/components/chat/parts/ReasoningPart";
+import { ReasoningPart } from "../../../../src/web/features/chat/parts/ReasoningPart";
 import { renderWithProviders } from "../../test-utils";
 
 describe("ReasoningPart", () => {