Move study editor state into StudyPage and hooks

- StudyPage owns layout/tabs/collapsed sections, tags, DOCX script
  import, chunk navigation, keyboard shortcuts, and the selected-chunk
  values derived from the project.
- useStudyResources: commentary + interlinear for the selected chunk's
  chapter. These now load only on the study page (they previously also
  fetched while on Setup).
- useCrossRefs: typed refs, dataset suggestions, verse text.
- useWordStudy: word entries, Strong's lookups, suggestion picker.
- Fix: study-page messages (word suggestions, DOCX import, lookups) set a
  status that only SetupPage displayed, so they were never seen. They
  now show as a toast on the study page.
- copyVerse moves into ReaderPage.
- Tests: toast, arrow-key navigation, cross-refs, tags.

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

src/hooks/useStudyResources.js

@@ -0,0 +1,76 @@
+// Commentary and interlinear text for the chapter of the selected chunk.
+// Each loads only while its section is expanded; results are cached for the visit.
+import { useEffect, useState } from 'react';
+
+const commentaryCache = {}; // "commentaryId/BOOK/chapter" -> data
+const interlinearCache = {}; // BOOK -> whole-book interlinear data
+
+export function useStudyResources({ project, selectedChunk, selectedChunkChapterIndex, collapsedSections }) {
+  const [commentarySource, setCommentarySource] = useState('matthew-henry');
+  const [commentaryData, setCommentaryData] = useState(null); // { content: [...] } for current chapter
+  const [commentaryLoading, setCommentaryLoading] = useState(false);
+  const [commentaryError, setCommentaryError] = useState('');
+  const [interlinearData, setInterlinearData] = useState(null);
+  const [interlinearLoading, setInterlinearLoading] = useState(false);
+  const [interlinearError, setInterlinearError] = useState('');
+
+  const loadInterlinearChapter = async (bookAbbrev, chapterNumber) => {
+    if (interlinearCache[bookAbbrev]) return interlinearCache[bookAbbrev];
+    const res = await fetch(`/interlinear/${bookAbbrev}.json`);
+    if (!res.ok) throw new Error('No interlinear data for this book.');
+    const data = await res.json();
+    interlinearCache[bookAbbrev] = data;
+    return data;
+  };
+
+  const loadCommentaryChapter = async (commentaryId, bookAbbrev, chapterNumber) => {
+    const cacheKey = `${commentaryId}/${bookAbbrev}/${chapterNumber}`;
+    if (commentaryCache[cacheKey]) return commentaryCache[cacheKey];
+    const res = await fetch(`https://bible.helloao.org/api/c/${commentaryId}/${bookAbbrev}/${chapterNumber}.json`);
+    const contentType = res.headers.get('content-type') || '';
+    if (!res.ok || !contentType.includes('json')) throw new Error(`No ${commentaryId} commentary for this chapter.`);
+    const data = await res.json();
+    commentaryCache[cacheKey] = data;
+    return data;
+  };
+
+  useEffect(() => {
+    if (collapsedSections.commentary) return;
+    if (selectedChunkChapterIndex < 0) return;
+    const chapter = project.chapters[selectedChunkChapterIndex];
+    setCommentaryLoading(true);
+    setCommentaryError('');
+    loadCommentaryChapter(commentarySource, chapter.bookAbbrev, chapter.chapter)
+      .then((data) => setCommentaryData(data))
+      .catch((err) => {
+        setCommentaryData(null);
+        setCommentaryError(err.message);
+      })
+      .finally(() => setCommentaryLoading(false));
+  }, [commentarySource, selectedChunk?.id, selectedChunkChapterIndex, collapsedSections.commentary]);
+
+  useEffect(() => {
+    if (collapsedSections.interlinear) return;
+    if (selectedChunkChapterIndex < 0) return;
+    const chapter = project.chapters[selectedChunkChapterIndex];
+    setInterlinearLoading(true);
+    setInterlinearError('');
+    loadInterlinearChapter(chapter.bookAbbrev, chapter.chapter)
+      .then((data) => setInterlinearData(data?.[String(chapter.chapter)] ?? null))
+      .catch((err) => {
+        setInterlinearData(null);
+        setInterlinearError(err.message);
+      })
+      .finally(() => setInterlinearLoading(false));
+  }, [selectedChunk?.id, selectedChunkChapterIndex, collapsedSections.interlinear]);
+
+  return {
+    commentarySource, setCommentarySource,
+    commentaryData,
+    commentaryLoading,
+    commentaryError,
+    interlinearData,
+    interlinearLoading,
+    interlinearError,
+  };
+}