fix(anki): keep existing maturity tier on re-mined notes

- appendFromNoteInfo no longer overwrites a note's tracked tier with 'new' when the note already has one recorded
- add test covering re-mining a note that already has a mature/learning tier

src/anki-integration/known-word-cache-maturity.test.ts

@@ -342,3 +342,33 @@ test('appendFromNoteInfo marks freshly mined notes as new tier', async () => {
     cleanup();
   }
 });
+
+test('appendFromNoteInfo preserves an existing maturity tier', async () => {
+  const { manager, clientState, cleanup } = createMaturityHarness(maturityConfig());
+
+  try {
+    clientState.findNotesByQuery.set('deck:"Mining"', [7, 8]);
+    clientState.findNotesByQuery.set('deck:"Mining" prop:ivl>=21', [7]);
+    clientState.findNotesByQuery.set('deck:"Mining" prop:ivl>=1 prop:ivl<21', []);
+    clientState.findNotesByQuery.set('deck:"Mining" is:learn', [8]);
+    clientState.notesInfoResult = [
+      { noteId: 7, fields: { Word: { value: '猫' } } },
+      { noteId: 8, fields: { Word: { value: '犬' } } },
+    ];
+    await manager.refresh(true);
+
+    manager.appendFromNoteInfo({
+      noteId: 7,
+      fields: { Word: { value: '子猫' } },
+    });
+    manager.appendFromNoteInfo({
+      noteId: 8,
+      fields: { Word: { value: '子犬' } },
+    });
+
+    assert.equal(manager.getKnownWordTier('子猫'), 'mature');
+    assert.equal(manager.getKnownWordTier('子犬'), 'learning');
+  } finally {
+    cleanup();
+  }
+});

src/anki-integration/known-word-cache.ts

@@ -342,7 +342,11 @@ export class KnownWordCacheManager {
     }
 
     // A just-mined card has never been reviewed.
-    if (this.isMaturityTrackingEnabled() && this.noteEntriesById.has(noteInfo.noteId)) {
+    if (
+      this.isMaturityTrackingEnabled() &&
+      this.noteEntriesById.has(noteInfo.noteId) &&
+      !this.noteTierById.has(noteInfo.noteId)
+    ) {
       this.noteTierById.set(noteInfo.noteId, 'new');
     }