feat(w3): ship v1.4.0 export matrix, cockpit tasks, and focus ambient

Add ExportMatrixService for txt/md/docx/pdf, extend ExportModal, cockpit outline tasks, focus ambient sound, and E2E-PDF-01 with 134 passing unit tests.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/renderer/components/settings/SettingsPage.tsx

@@ -234,6 +234,19 @@ export function SettingsPage(): React.JSX.Element {
                 {t('settings.goalNotifications')}
               </label>
             </div>
+            <div className="setting-item">
+              <label style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
+                <input
+                  type="checkbox"
+                  data-testid="settings-focus-ambient"
+                  checked={settings.enableFocusAmbientSound === true}
+                  onChange={(e) =>
+                    void settings.update({ enableFocusAmbientSound: e.target.checked })
+                  }
+                />
+                {t('settings.focusAmbientSound')}
+              </label>
+            </div>
             <div className="setting-item">
               <span>{t('settings.extractThreshold')}</span>
               <input
@@ -263,7 +276,7 @@ export function SettingsPage(): React.JSX.Element {
         {section === 'shortcuts' && <ShortcutEditor />}
         {section === 'about' && (
           <p style={{ color: 'var(--text-secondary)', lineHeight: 1.8 }}>
-            {t('app.name')} v1.3.0
+            {t('app.name')} v1.4.0
             <br />
             {t('app.tagline')}
           </p>