fix: resolve all TS errors, ESLint warnings, and npm warnings bump to v0.3.12

- Pin all @milkdown/* packages to exact 7.21.1, add phantom-dep plugins as direct deps

- Fix TextSelection.create type error in useMilkdown.ts

- Fix Backspace auto-pair dead-code bug (unreachable due to PAIRS check order)

- Extract parseHeadings/Heading to outlineUtils.ts (react-refresh fix)

- Extract StatusBar item components to StatusBarItems.tsx (react-refresh fix)

- Configure npm allowScripts for electron and esbuild postinstall

- Update QUALITY_REVIEW_REPORT.json with all fixes applied

- Bump version to 0.3.12

src/renderer/hooks/useStatusBarItems.tsx

@@ -1,69 +1,12 @@
 import { useEffect } from 'react'
 import { useStatusBarStore } from '../stores/statusBarStore'
-import { useTabStore } from '../stores/tabStore'
-import { useEditorStore } from '../stores/editorStore'
-import { useDocStats } from './useDocStats'
-import { getFileName } from '../lib/fileUtils'
-import { LoadingSpinner } from '../components/LoadingSpinner/LoadingSpinner'
-
-/** 文件信息 — 文件名或"就绪" */
-function FileInfoItem() {
-  const activeTab = useTabStore(s => s.getActiveTab())
-  return (
-    <span id="status-text">
-      {activeTab ? (activeTab.filePath ? getFileName(activeTab.filePath) : '未命名') : '就绪'}
-    </span>
-  )
-}
-
-/** 加载指示器 — 打开文件/加载目录/渲染中 */
-function LoadingItem() {
-  const loadingStates = useEditorStore(s => s.loadingStates)
-  const hasLoading = Object.values(loadingStates).some(Boolean)
-  if (!hasLoading) return null
-
-  const label = loadingStates['file-open']
-    ? '正在打开文件...'
-    : loadingStates['dir-load']
-      ? '正在加载目录...'
-      : loadingStates['markdown-render']
-        ? '正在渲染...'
-        : ''
-
-  return (
-    <span className="status-loading" aria-busy="true">
-      <LoadingSpinner size="small" />
-      <span>{label}</span>
-    </span>
-  )
-}
-
-/** 文档统计 — 行数 / 词数 / 字符数 */
-function DocStatsItem() {
-  const activeTab = useTabStore(s => s.getActiveTab())
-  const stats = useDocStats(activeTab?.content)
-  if (!activeTab) return null
-
-  return (
-    <>
-      <span className="status-stat" title="行数" aria-label={`${stats.lines} 行`}>{stats.lines} 行</span>
-      <span className="status-divider">|</span>
-      <span className="status-stat" title="单词数" aria-label={`${stats.words} 个单词`}>{stats.words} 词</span>
-      <span className="status-divider">|</span>
-      <span className="status-stat" title="字符数（含空格）" aria-label={`${stats.chars} 个字符`}>{stats.chars} 字符</span>
-    </>
-  )
-}
-
-/** 静态项 — 编码 */
-function EncodingItem() {
-  return <span id="status-encoding">UTF-8</span>
-}
-
-/** 静态项 — 语言 */
-function LangItem() {
-  return <span id="status-lang">Markdown</span>
-}
+import {
+  FileInfoItem,
+  LoadingItem,
+  DocStatsItem,
+  EncodingItem,
+  LangItem
+} from '../components/StatusBar/StatusBarItems'
 
 /**
  * useDefaultStatusBarItems — 注册所有默认状态栏项（不含 auto-save）。