A couple of fixes

src/RecentBooksStore.h

@@ -17,7 +17,8 @@ struct RecentBook {
   int8_t fontFamilyOverride = -1;
   // -1 = use global setting, otherwise CrossPointSettings::FONT_SIZE value.
   int8_t fontSizeOverride = -1;
-  bool bionicReadingOverride = false;
+  // -1 = use global default, otherwise explicit per-book override (0 = off, 1 = on).
+  int8_t bionicReadingOverride = -1;
 
   bool operator==(const RecentBook& other) const { return path == other.path; }
 };