fix: make new project action reset dashboard composer

src/features/dashboard/dashboard-lib.test.ts

@@ -1,6 +1,11 @@
 import { describe, expect, it } from 'vitest'
 
-import { THEME_PREFERENCE_CHIPS, THEME_PREFERENCES } from './dashboard-lib'
+import {
+  THEME_PREFERENCE_CHIPS,
+  THEME_PREFERENCES,
+  createNewProjectComposerState,
+  isNewProjectActionDisabled,
+} from './dashboard-lib'
 
 describe('dashboard theme preferences', () => {
   it('exposes only explicit theme preferences instead of business templates', () => {
@@ -22,3 +27,19 @@ describe('dashboard theme preferences', () => {
     })
   })
 })
+
+describe('dashboard new project action', () => {
+  it('resets the composer to a clean draft with the default theme', () => {
+    expect(createNewProjectComposerState()).toEqual({
+      prompt: '',
+      inputError: null,
+      selectedTheme: THEME_PREFERENCE_CHIPS[0].id,
+    })
+  })
+
+  it('is disabled while projects are loading or a project is being created', () => {
+    expect(isNewProjectActionDisabled({ creating: false, loading: true })).toBe(true)
+    expect(isNewProjectActionDisabled({ creating: true, loading: false })).toBe(true)
+    expect(isNewProjectActionDisabled({ creating: false, loading: false })).toBe(false)
+  })
+})

src/features/dashboard/dashboard-lib.ts

@@ -24,6 +24,32 @@ export const THEME_PREFERENCE_CHIPS = [
 
 export type ThemePreferenceId = (typeof THEME_PREFERENCE_CHIPS)[number]['id']
 
+export type NewProjectComposerState = {
+  prompt: string
+  inputError: null
+  selectedTheme: ThemePreferenceId
+}
+
+/** 新建项目入口始终回到干净的 Composer 草稿。 */
+export function createNewProjectComposerState(): NewProjectComposerState {
+  return {
+    prompt: '',
+    inputError: null,
+    selectedTheme: THEME_PREFERENCE_CHIPS[0].id,
+  }
+}
+
+/** 本地项目尚未加载完成或已有创建任务时，不允许再次开始新项目。 */
+export function isNewProjectActionDisabled({
+  creating,
+  loading,
+}: {
+  creating: boolean
+  loading: boolean
+}): boolean {
+  return creating || loading
+}
+
 /**
  * 主题选项 → PlannerInput.themePreference 映射。当前只提供舒适密度，
  * 与产品规格默认的 neutral / comfortable 保持一致；颜色预设由用户明确选择。

src/features/dashboard/dashboard-page.tsx

@@ -22,7 +22,9 @@ import {
   THEME_PREFERENCES,
   THEME_PREFERENCE_CHIPS,
   TOO_LONG_INPUT_MESSAGE,
+  createNewProjectComposerState,
   deriveTitleFromPrompt,
+  isNewProjectActionDisabled,
   type ThemePreferenceId,
 } from './dashboard-lib'
 import { ExamplePromptList } from './example-prompt-list'
@@ -55,6 +57,7 @@ export function DashboardPage() {
 
   const textareaRef = useRef<HTMLTextAreaElement | null>(null)
   const menuButtonRef = useRef<HTMLButtonElement | null>(null)
+  const restoreMenuFocusRef = useRef(true)
 
   const loadProjects = useCallback(async () => {
     setLoadState('loading')
@@ -119,13 +122,24 @@ export function DashboardPage() {
     window.addEventListener('keydown', handleKeyDown)
     return () => {
       window.removeEventListener('keydown', handleKeyDown)
-      menuButtonRef.current?.focus()
+      if (restoreMenuFocusRef.current) {
+        menuButtonRef.current?.focus()
+      }
+      restoreMenuFocusRef.current = true
     }
   }, [drawerOpen])
 
-  const focusComposer = useCallback(() => {
+  const handleNewProject = useCallback(() => {
+    const nextComposer = createNewProjectComposerState()
+    setPrompt(nextComposer.prompt)
+    setInputError(nextComposer.inputError)
+    setSelectedTheme(nextComposer.selectedTheme)
     window.scrollTo({ top: 0, behavior: 'smooth' })
-    textareaRef.current?.focus()
+
+    // 等待状态更新和移动端抽屉卸载完成，再把焦点交给 Composer。
+    window.requestAnimationFrame(() => {
+      textareaRef.current?.focus()
+    })
   }, [])
 
   const handlePickExample = useCallback(
@@ -184,6 +198,10 @@ export function DashboardPage() {
     updatedAt: project.updatedAt,
     phase: project.phase,
   }))
+  const newProjectDisabled = isNewProjectActionDisabled({
+    creating,
+    loading: loadState === 'loading',
+  })
 
   return (
     <>
@@ -213,8 +231,8 @@ export function DashboardPage() {
       <SidebarNavigation
         projects={sidebarProjects}
         loading={loadState === 'loading'}
-        newProjectDisabled={creating}
-        onNewProject={focusComposer}
+        newProjectDisabled={newProjectDisabled}
+        onNewProject={handleNewProject}
       />
 
       {drawerOpen ? (
@@ -223,10 +241,11 @@ export function DashboardPage() {
           <SidebarNavigation
             projects={sidebarProjects}
             loading={loadState === 'loading'}
-            newProjectDisabled={creating}
+            newProjectDisabled={newProjectDisabled}
             onNewProject={() => {
+              restoreMenuFocusRef.current = false
               setDrawerOpen(false)
-              focusComposer()
+              handleNewProject()
             }}
             variant="drawer"
             onNavigate={() => setDrawerOpen(false)}