v2.0.2 — English tag aliases, English-only website, undo-body flaky fix

- tags: accept #birthday and #appointment as English synonyms for
  #geburtstag and #termin. Normalised to the German canonical form at
  extractTags() write-time so every downstream check (parseTags /
  calendar logic / board filters) keeps working without per-call-site
  aliasing. Editor body-regex extended so the "new appointment"
  heuristic and auto-sync trigger on either variant.
- website: replace #termin/#geburtstag with #appointment/#birthday in
  tag chips, calendar feature list, and calendar legend.
- tests: fix flaky "Undo: Editor Save → Ctrl+Z reverts body change"
  that raced doSave(). The test polled the server for the patched body
  and fired Ctrl+Z as soon as it landed, but the undo shortcut is
  guarded by !guards.isOpen('modal'), and closeModal() only runs after
  the post-patch _reloadAll — on fast servers the key was swallowed.
  Poll now also waits for the modal `.open` class to drop.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

public/plugins/tests/undo.test.js

@@ -109,11 +109,17 @@ describe('Undo: Editor Save', () => {
         bodyEl.dispatchEvent(new Event('input', { bubbles: true }));
         click('#modal-save-close');
 
+        // Wait for both the server patch AND the modal close before firing
+        // Ctrl+Z — the global undo shortcut is guarded by
+        // `!guards.isOpen('modal')`, so if doSave's closeModal() hasn't run
+        // yet (it only fires after the post-save _reloadAll), the undo key
+        // is swallowed silently and the test races the client's save flow.
         let card;
         for (let i = 0; i < 40; i++) {
             await sleep(100);
             card = (await fetch(`api/cards?ids=${res.id}`).then(r => r.json())).find(c => c.id == res.id);
-            if ((card?.body || '').includes('after edit')) break;
+            const modalClosed = !document.getElementById('modal')?.classList.contains('open');
+            if ((card?.body || '').includes('after edit') && modalClosed) break;
         }
         expect(card.body).toContain('after edit');