Add own-work tracking, Claude hand-off check, and weekly recall

- Long pastes into Observe/Interpret/Apply are tagged as pasted; notes show
  Mine / N pasted and an own-words share. Pastes follow text through merges.
- The "-> Claude" buttons on the Script stage ask first when a chunk lacks
  enough of the user's own (non-pasted) words.
- Weekly recall card on Home: write a passage from memory, compare with notes,
  self-rate; recalls are saved on the chunk and synced.
- Recall history on Home with an eight-week strip and the full list.

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

src/hooks/useProjectLibrary.js

@@ -221,6 +221,32 @@ export function useProjectLibrary({
     });
   };
 
+  // Saves a weekly recall (what you remembered, and how it went) on one chunk of a stored study.
+  const saveChunkRecall = (id, chunkId, recall) => {
+    const loaded = loadProjectById(id);
+    if (!loaded) return;
+    const updated = {
+      ...loaded,
+      lastEdited: Date.now(),
+      chapters: loaded.chapters.map((ch) => ({
+        ...ch,
+        chunks: ch.chunks.map((c) => (c.id === chunkId ? { ...c, recalls: [...(c.recalls ?? []), recall] } : c)),
+      })),
+    };
+    saveProjectToStorage(updated);
+    unsyncedStudies.add(id);
+    setProjectIndex(loadProjectIndex());
+    if (project?.id === id) setProject(updated);
+    saveRemoteProject(updated, { baseEdited: getSyncBase(id) }).then((result) => {
+      if (result.ok) {
+        const serverEdited = result.data?.lastEdited ?? updated.lastEdited;
+        setSyncBase(id, serverEdited);
+        unsyncedStudies.remove(id);
+        try { saveProjectToStorage({ ...updated, lastEdited: serverEdited }); setProjectIndex(loadProjectIndex()); } catch { /* already saved */ }
+      } else if (result.status === 409) toast('That study changed on another device. Open it to choose which version to keep.', { tone: 'error' });
+    });
+  };
+
   // Deleting is immediate here, with an Undo for a few seconds; only after that is the server copy
   // removed (and straight away if the tab is closed first, so a deleted project never comes back).
   const finishDelete = (id) => {
@@ -287,6 +313,7 @@ export function useProjectLibrary({
     openStudyChunk,
     renameProjectInStorage,
     setProjectSeries,
+    saveChunkRecall,
     deleteProject,
     pullLatestFromServer,
   };