Ship native iOS app, Wiki/TTS backend, and skeleton loading UX.

Replace the WebView shell with SwiftUI screens, add account-scoped Wiki and TTS APIs with adaptive review and photo scan support, and keep web/iOS pages usable while data loads asynchronously.

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

backend/routers/settings_router.py

@@ -20,6 +20,7 @@ def get_settings(
         daily_target=s.daily_target,
         master_required_count=s.master_required_count,
         weak_wrong_threshold=s.weak_wrong_threshold,
+        error_clear_correct_count=s.error_clear_correct_count,
     )
 
 
@@ -36,10 +37,13 @@ def update_settings(
         s.master_required_count = data.master_required_count
     if data.weak_wrong_threshold is not None:
         s.weak_wrong_threshold = data.weak_wrong_threshold
+    if data.error_clear_correct_count is not None:
+        s.error_clear_correct_count = data.error_clear_correct_count
     db.commit()
     db.refresh(s)
     return SettingsOut(
         daily_target=s.daily_target,
         master_required_count=s.master_required_count,
         weak_wrong_threshold=s.weak_wrong_threshold,
+        error_clear_correct_count=s.error_clear_correct_count,
     )