refactor(data): merge DTO models into schemas

src/stores/chat/__tests__/chat-history-flow.test.ts

@@ -1,7 +1,7 @@
 import { describe, expect, it } from "vitest";
 import { createActor, fromCallback, waitFor } from "xstate";
 
-import type { UiMessage } from "@/data/dto/chat";
+import type { UiMessage } from "@/stores/chat/ui-message";
 import type { ChatEvent } from "@/stores/chat/chat-events";
 import { chatMachine } from "@/stores/chat/chat-machine";
 import type { LoadMoreHistoryActorEvent } from "@/stores/chat/machine/actors/history";