Redesign the Reader; add ESV

New reading surface with paper/sepia/dark themes, slim top and bottom bars,
and sheets for navigation, search, settings, audio and per-verse study tools.
Plan progress is built into the reader. Page-flip mode removed. ESV added via
the server-side proxy (ESV_API_KEY).

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/components/StudyPanel.jsx

@@ -5,7 +5,7 @@ import {
   COMMENTARIES, loadCommentary, loadTheographic, loadPerson, pickCommentaryEntry, useAsync,
 } from '../hooks/useVerseStudy.js';
 
-function CommentaryTab({ book, chapter, verse }) {
+export function CommentaryTab({ book, chapter, verse }) {
   const [sourceId, setSourceId] = useState(() => {
     try { return localStorage.getItem('reader-commentary') || COMMENTARIES[0].id; } catch { return COMMENTARIES[0].id; }
   });
@@ -77,7 +77,7 @@ function PersonCard({ person }) {
   );
 }
 
-function PeoplePlacesTab({ book, chapter, verse }) {
+export function PeoplePlacesTab({ book, chapter, verse }) {
   const { status, data } = useAsync(() => loadTheographic(book, chapter), [book, chapter]);
   if (status === 'loading') return <p className="text-xs text-slate-500">Loading…</p>;
   if (status === 'empty') return <p className="text-xs text-slate-500">No people or places data for this chapter.</p>;