Add cross-reference map, admin health page, passkeys and device list, settings tabs

- Reader: chapter cross-reference map (M) from IQ Bible's reference graph
- Admin: Health tab with disk use, snapshots (back up, download, restore), failure logs
- Passkey sign-in (WebAuthn), signed-in device list, sign out others, optional sign-in alerts
- Settings split into Account, Preferences, Notifications, Security, Your data tabs
- ntfy server field: catch a topic typed into the server box

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

src/components/reader/VerseSheet.jsx

@@ -156,7 +156,7 @@ function CompareTab({ book, chapter, verse, current }) {
 
 export default function VerseSheet({
   verse, book, bookName, chapter, translation, words, crossRefs, crossRefsLoading, onLoadCrossRefs,
-  bookmarkColor, onToggleBookmark, onCycleColor, bookmarkNote = '', onSetBookmarkNote, onSetHighlightNote, studiesHere = [], onOpenStudy, onPray, onJump, onClose, request,
+  bookmarkColor, onToggleBookmark, onCycleColor, bookmarkNote = '', onSetBookmarkNote, onSetHighlightNote, studiesHere = [], onOpenStudy, onPray, onOpenMap, onJump, onClose, request,
   verseHighlights = [], colorLabels = {}, onHighlightVerse, onClearVerseHighlights, panelRef, resizeHandle,
 }) {
   const iqOn = useIqAvailable();
@@ -291,6 +291,7 @@ export default function VerseSheet({
       {tab === 'commentary' && <CommentaryTab book={book} chapter={chapter} verse={verse.number} />}
       {tab === 'compare' && <CompareTab book={book} chapter={chapter} verse={verse.number} current={translation} />}
       {tab === 'original' && <OriginalTab words={words} />}
+      {tab === 'refs' && onOpenMap && <button type="button" onClick={onOpenMap} className="mb-3 rounded-lg border border-[var(--r-line)] px-3 py-1.5 text-xs hover:bg-black/5">Map this chapter’s links (M)</button>}
       {tab === 'refs' && (
         <RefsTab refs={crossRefs} loading={crossRefsLoading} active={preview} onPick={setPreview}
           preview={preview && <RefPreview refItem={preview} translation={translation} onOpen={onJump} onClose={() => setPreview(null)} />} />