fix: update the sync settings' collection count after the chooser listed new ones #34

The account row in the sync settings counts the synced address books
or calendars from its own copy of the list, loaded when the row
appears. The chooser loads a fresh list when it opens, so a calendar
created meanwhile showed there but not in the count ("4 of 5 sync"
stayed after a sixth appeared, and turning it on or off changed
nothing) until the settings page was opened again.

Every fresh list now reaches every view of that account's collections,
so the count follows the chooser.

src/components/settings/device-sync/use-sync-collections.ts

@@ -7,6 +7,7 @@ import {
   cachedSyncCollections,
   CollectionsError,
   listSyncCollections,
+  onSyncCollectionsLoaded,
   type CollectionsErrorKind,
   type SyncCollection,
 } from '../../../device-sync/app/collections';
@@ -56,6 +57,14 @@ export function useSyncCollections(registryId: string, authority: Authority, act
     return () => { cancelled = true; };
   }, [registryId, authority, active, attempt, feeds]);
 
+  // The chooser loads its own, fresher list: the row's counts follow it.
+  React.useEffect(
+    () => onSyncCollectionsLoaded((id, auth, collections) => {
+      if (id === registryId && auth === authority) setState({ kind: 'loaded', collections });
+    }),
+    [registryId, authority],
+  );
+
   const reload = React.useCallback(() => setAttempt((n) => n + 1), []);
   return { state, reload };
 }