merge: integrate coding default page

# Conflicts:
#	src/components/layout/Sidebar.tsx
#	tests/unit/coding-chat-panel.test.tsx

tests/unit/coding-chat-panel.test.tsx

@@ -60,6 +60,12 @@ const project: CodingProjectSummary = {
   updatedAt: '2026-08-23T00:00:00.000Z',
   lastOpenedAt: '2026-08-23T00:00:00.000Z',
 };
+const secondProject: CodingProjectSummary = {
+  ...project,
+  id: 'project-2',
+  name: 'Second local project',
+  lastOpenedAt: '2026-08-22T00:00:00.000Z',
+};
 const agent: CodingProjectAgent = {
   id: 'agent-1',
   avatarId: 'default',
@@ -217,6 +223,40 @@ describe('CodingChatPanel first Conversation', () => {
     expect(openProjectSettings).toHaveBeenCalledOnce();
   });
 
+  it('shows a branded create CTA and horizontal existing-project cards before a project is selected', async () => {
+    projectApi.list.mockResolvedValue({ projects: [project, secondProject], activeProjectId: null });
+    const onCreateProject = vi.fn();
+    const onOpenProject = vi.fn();
+    const onOpenProjectSettings = vi.fn();
+    const { CodingChatPanel } = await import('@/pages/Chat/CodingChatPanel');
+
+    render(
+      <CodingChatPanel
+        onCreateProject={onCreateProject}
+        onOpenProject={onOpenProject}
+        onOpenProjectSettings={onOpenProjectSettings}
+      />,
+    );
+
+    expect(await screen.findByTestId('coding-chat-empty-project')).toBeInTheDocument();
+    expect(screen.getByRole('heading', { name: '你想让麦洛和你一起构建什么？' })).toBeInTheDocument();
+    expect(screen.getByRole('img', { name: '麦洛 M 标识' })).toBeInTheDocument();
+    expect(screen.getByRole('button', { name: '新增项目' })).toBeInTheDocument();
+    expect(screen.getByTestId('coding-existing-projects')).toHaveTextContent('Local project');
+    expect(screen.getByTestId('coding-existing-projects')).toHaveTextContent('Second local project');
+    expect(screen.queryByText('已有项目')).not.toBeInTheDocument();
+    expect(screen.queryByText('选择一个项目继续')).not.toBeInTheDocument();
+    expect(screen.queryByTestId('coding-project-starter')).not.toBeInTheDocument();
+    expect(screen.queryByRole('button', { name: '项目与插件设置' })).not.toBeInTheDocument();
+
+    fireEvent.click(screen.getByTestId('coding-start-project-button'));
+    expect(onCreateProject).toHaveBeenCalledOnce();
+
+    fireEvent.click(screen.getByRole('button', { name: '进入项目 Second local project' }));
+    expect(onOpenProject).toHaveBeenCalledWith(secondProject.id);
+    expect(onOpenProjectSettings).not.toHaveBeenCalled();
+  });
+
   it('makes the first-Conversation textarea editable while runtime metadata is held', async () => {
     projectApi.list.mockResolvedValue({ projects: [project], activeProjectId: project.id });
     projectApi.config.mockResolvedValue({ project, config });
@@ -233,6 +273,8 @@ describe('CodingChatPanel first Conversation', () => {
     const view = render(<CodingChatPanel />);
 
     const textbox = await screen.findByRole('textbox');
+    expect(screen.getByRole('heading', { name: '你想让麦洛和你一起构建什么？' })).toBeInTheDocument();
+    expect(screen.getByRole('img', { name: '麦洛 M 标识' })).toBeInTheDocument();
     expect(textbox).toBeEnabled();
     expect(projectApi.create).toHaveBeenCalledOnce();
     expect(conversationApi.snapshot).toHaveBeenCalledWith(conversation.id);
@@ -940,7 +982,7 @@ describe('CodingChatPanel first Conversation', () => {
       target: { files },
     });
     expect(await screen.findByText('每条消息最多添加 16 张图片。')).toBeInTheDocument();
-    expect(screen.getAllByRole('img')).toHaveLength(16);
+    expect(screen.getAllByRole('img', { name: /^image-\d+\.png$/u })).toHaveLength(16);
     expect(codingConversationStore.getState().entriesByConversationId[conversation.id])
       .toMatchObject({ loadState: 'live', error: null });
     await waitFor(() => expect(screen.getByRole('button', { name: '发送' })).toBeEnabled());

tests/unit/coding-project-entry.test.ts

@@ -0,0 +1,33 @@
+import { describe, expect, it, vi } from 'vitest';
+import {
+  requestCodingProjectCreation,
+  requestCodingProjectOpen,
+  subscribeCodingProjectCreationRequest,
+  subscribeCodingProjectOpenRequest,
+} from '@/lib/coding-project-entry';
+
+describe('coding project entry events', () => {
+  it('delivers project creation requests and removes the listener on unsubscribe', () => {
+    const listener = vi.fn();
+    const unsubscribe = subscribeCodingProjectCreationRequest(listener);
+
+    requestCodingProjectCreation();
+    expect(listener).toHaveBeenCalledOnce();
+
+    unsubscribe();
+    requestCodingProjectCreation();
+    expect(listener).toHaveBeenCalledOnce();
+  });
+
+  it('delivers the selected project id and ignores requests after unsubscribe', () => {
+    const listener = vi.fn();
+    const unsubscribe = subscribeCodingProjectOpenRequest(listener);
+
+    requestCodingProjectOpen('project-2');
+    expect(listener).toHaveBeenCalledWith('project-2');
+
+    unsubscribe();
+    requestCodingProjectOpen('project-3');
+    expect(listener).toHaveBeenCalledOnce();
+  });
+});