feat(settings): replicate the WorkBuddy about and help panels without external jumps (TODO 19)

Recover the shared WorkBuddy 5.8.3 HelpFeedbackPanel stylesheet through REA (18 module rules plus scoped light/dark tokens) and rebuild the 关于 and 获取帮助 pages: 638x620 panels, 638x108 two-row cards, 82x32/102x32 actions, the 638x226 follow card with three 120x120 QR frames and the 638x44 footer.

Keep the user's no-jump requirement explicit: every external entry (检查更新, 前往官网, 填写反馈, 查看文档, 隐私政策, 服务协议) keeps the original wording and geometry but is aria-disabled with a 暂未接入/尚未配置 tooltip and performs no navigation; the WorkBuddy account QR codes become same-size 尚未配置 placeholders. The version line reads the real appInfo version.

Also fix a CSS bundling regression found while wiring this page: the shared general-settings stylesheet was inlined three times and overrode the personalization long-card padding, collapsing the 598x160 previews to 614 wide. Remove the duplicate import and raise the personalization padding specificity.

Verify with scripts/verify-about-help-settings.cjs (15 assertions: both pages, geometry, real version, disabled jumpless actions, no anchors, dark surfaces) and keep all existing settings regressions green.

scripts/verify-settings-nav.cjs

@@ -125,10 +125,10 @@ if (!process.versions.electron) {
     // 原版 4 组；about 组按组件约定渲染为分隔线而不是标题。
     check('nav keeps the four recovered groups', [nav.groups.length, nav.dividers], [3, 1])
     // 通用(settings) 在 TODO 10 接入后同样可用。
-    const expectedDisabled = EXPECTED_TABS.filter(tab => !['settings', 'models', 'appearance', 'keyboardShortcuts', 'personalization'].includes(tab))
+    const expectedDisabled = EXPECTED_TABS.filter(tab => !['settings', 'models', 'appearance', 'keyboardShortcuts', 'personalization', 'helpFeedback', 'getHelp'].includes(tab))
     check('unwired entries stay disabled', nav.tabs.filter((tab, index) => nav.disabled[index] === 'true'), expectedDisabled)
     check('unwired entries keep the 暂未接入 hint', nav.titles.filter(title => (title ?? '').includes('暂未接入')).length, expectedDisabled.length)
-    check('settings, appearance, keyboard shortcuts, personalization and models stay enabled', nav.tabs.filter((tab, index) => !nav.disabled[index]), ['settings', 'appearance', 'keyboardShortcuts', 'personalization', 'models'])
+    check('settings, appearance, shortcuts, personalization, models, about and help stay enabled', nav.tabs.filter((tab, index) => !nav.disabled[index]), ['settings', 'appearance', 'keyboardShortcuts', 'personalization', 'models', 'helpFeedback', 'getHelp'])
 
     await step('settings-search-excludes-removed')
     await read(`(()=>{const input=document.querySelector('.settings-navigation input[type="search"]');