Add dark mode persistence and book name formatting for professional display

frontend/src/components/ChapterSelector.tsx

@@ -6,9 +6,10 @@ interface ChapterSelectorProps {
   book: string;
   onChapterSelect: (chapter: string) => void;
   onBack: () => void;
+  formatBookName: (bookName: string) => string;
 }
 
-const ChapterSelector: React.FC<ChapterSelectorProps> = ({ book, onChapterSelect, onBack }) => {
+const ChapterSelector: React.FC<ChapterSelectorProps> = ({ book, onChapterSelect, onBack, formatBookName }) => {
   const [chapters, setChapters] = useState<string[]>([]);
   const [loading, setLoading] = useState(true);
 
@@ -69,7 +70,7 @@ const ChapterSelector: React.FC<ChapterSelectorProps> = ({ book, onChapterSelect
       {/* Book Title */}
       <div className="text-center mb-8">
         <h1 className="text-3xl font-bold text-gray-900 dark:text-gray-100 mb-2">
-          {book}
+          {formatBookName(book)}
         </h1>
         <p className="text-lg text-gray-600 dark:text-gray-400">
           Select a chapter to read