App quality: offline badge, per-note history, keyboard study mode, notes import

- Study cards say whether the Bible text works offline, with a button to save
  the missing book (notes are always kept on the device).
- Each note keeps its last 12 versions with Restore (History under each note).
- Keyboard-only study: 1/2/3 write in Observe/Interpret/Apply, C/W/X/P switch
  resource tabs, V compares, Esc leaves a note box; listed under "?".
- Export > Import notes: bring Word/Markdown/text notes into the matching
  chunks without overwriting anything; can mark them as not your own.

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

src/utils/offline.js

@@ -43,3 +43,18 @@ export async function downloadChapters(translation, refs, { onProgress, signal,
   await Promise.all(Array.from({ length: Math.min(concurrency, refs.length) }, worker));
   return { done, failed };
 }
+
+// What a study needs from the network to open offline. Your notes are always kept on this device; only the
+// Bible text must have been saved. `saved` is loadSavedBooks(). -> { state: 'ready' | 'partial' | 'licensed',
+// translation, missing: [{ abbrev, name }] }
+export function offlineStatus(project, saved = loadSavedBooks()) {
+  const translation = project?.translation ?? 'BSB';
+  if (!canSaveOffline(translation)) return { state: 'licensed', translation, missing: [] };
+  const books = [];
+  for (const chapter of project?.chapters ?? []) {
+    if (chapter.bookAbbrev && !books.some((b) => b.abbrev === chapter.bookAbbrev)) books.push({ abbrev: chapter.bookAbbrev, name: chapter.book });
+  }
+  const have = saved[translation] ?? [];
+  const missing = books.filter((b) => !have.includes(b.abbrev));
+  return { state: missing.length ? 'partial' : 'ready', translation, missing };
+}