Implement account deletion

lib/ui/state/core.dart

@@ -193,8 +193,7 @@ class CoreCubit extends Cubit<CoreState> {
 
     cancelStreams();
     try {
-      // TODO
-      //await db.deleteAccount(account);
+      await GetIt.I.get<OkaneDatabase>().accountsDao.removeAccount(account);
     } finally {
       emit(state.copyWith(isDeletingAccount: false));
     }