log date and title on store update and delete

uid-only log lines made it hard to tell what was being processed;
date + title give enough context to read the log as a data-flow narrative.

room_cal/store/_caldav.py

@@ -296,13 +296,15 @@ class CalDAVBackend:
       raw.data = ical.to_ical().decode('utf-8')
       await raw.save()
     self._cal._event_cache.clear()
-    _log.info('update uid=%s', uid)
-    return _dict_to_record(_parse_event(raw))
+    result = _dict_to_record(_parse_event(raw))
+    _log.info('update date=%s title=%r', result.start.date(), result.title)
+    return result
 
   async def delete(self, uid: str) -> None:
     async with await self._cal._client() as client:
       cal = await self._cal._get_calendar(client)
       raw = await cal.event_by_uid(uid)
+      deleted = _dict_to_record(_parse_event(raw))
       await raw.delete()
     self._cal._event_cache.clear()
-    _log.info('delete uid=%s', uid)
+    _log.info('delete date=%s title=%r', deleted.start.date(), deleted.title)

room_cal/store/_sqlite.py

@@ -129,12 +129,16 @@ class SQLiteBackend:
       await db.commit()
       cursor = await db.execute(f'SELECT {_COLS} FROM events WHERE uid = ?', (uid,))
       row = await cursor.fetchone()
-    _log.info('update uid=%s', uid)
-    return self._to_record(row)
+    result = self._to_record(row)
+    _log.info('update date=%s title=%r', result.start.date(), result.title)
+    return result
 
   async def delete(self, uid: str) -> None:
     async with self._connect() as db:
       await db.execute(_CREATE_TABLE)
+      cursor = await db.execute(f'SELECT {_COLS} FROM events WHERE uid = ?', (uid,))
+      row = await cursor.fetchone()
+      deleted = self._to_record(row) if row else None
       await db.execute('DELETE FROM events WHERE uid = ?', (uid,))
       await db.commit()
-    _log.info('delete uid=%s', uid)
+    _log.info('delete date=%s title=%r', deleted.start.date() if deleted else '?', deleted.title if deleted else uid)