fix(notifications): remove redundant rollback optional chain

The rollback guard already narrows the captured prior notification state.
Call forEach directly to satisfy the type-aware lint rule.

All 61 focused tests, full formatting and source review pass. Final-head
static checks and remaining aggregate validation are still pending.

web/app/composables/api/useNotificationAPI.ts

@@ -168,7 +168,7 @@ export default function () {
 			}
 
 			// rollback
-			oldNotifs?.forEach(({ key, data }) => {
+			oldNotifs.forEach(({ key, data }) => {
 				queryCache.setQueryData(key, data)
 			})
 		},