feat(sync): follow the visit sync on the dashboard

Show the "Syncing with Steam" badge while a visit sync runs, then
reload the sync changes banner and the library.

src/utils/syncChanges.test.js

@@ -16,6 +16,10 @@ describe('bannerOf', () => {
         expect(bannerOf(result())).toBeNull();
     });
 
+    it('showsNothingForAnEmptyLoginSync', () => {
+        expect(bannerOf(result({startedBy: 'LOGIN'}))).toBeNull();
+    });
+
     it('saysNothingChangedForAnEmptyManualSync', () => {
         expect(bannerOf(result({startedBy: 'MANUAL'}))).toEqual({mode: 'nothing'});
     });