refactor(models): migrate 28 data models to Zod schema-driven pattern

src/data/models/chat/chat_history_response.ts

@@ -1,60 +1,41 @@
 /**
  * 聊天历史响应
  * 原始 Dart: ChatHistoryResponse (lib/data/models/chat/chat_response.dart)
- *
- * 注：原始 Dart 中 `total` 为 `int?`，按"全部非空"约定兜底为 0。
  */
-import { ChatMessage } from "./chat_message";
+import { z } from "zod";
+import { ChatMessage, ChatMessageSchema } from "./chat_message";
+
+export const ChatHistoryResponseSchema = z.object({
+  messages: z.array(ChatMessageSchema),
+  total: z.number().default(0),
+  limit: z.number(),
+  offset: z.number(),
+});
+
+export type ChatHistoryResponseInput = z.input<typeof ChatHistoryResponseSchema>;
+export type ChatHistoryResponseData = z.output<typeof ChatHistoryResponseSchema>;
 
 export class ChatHistoryResponse {
-  readonly messages: ChatMessage[];
-  readonly total: number;
-  readonly limit: number;
-  readonly offset: number;
+  declare readonly messages: ChatMessage[];
+  declare readonly total: number;
+  declare readonly limit: number;
+  declare readonly offset: number;
 
-  constructor(params: {
-    messages: ChatMessage[];
-    total?: number;
-    limit: number;
-    offset: number;
-  }) {
-    this.messages = params.messages;
-    this.total = params.total ?? 0;
-    this.limit = params.limit;
-    this.offset = params.offset;
+  private constructor(input: ChatHistoryResponseInput) {
+    const data = ChatHistoryResponseSchema.parse(input);
+    Object.assign(this, data);
     Object.freeze(this);
   }
 
-  toJson(): Record<string, unknown> {
-    return {
-      messages: this.messages.map((m) => m.toJson()),
-      total: this.total,
-      limit: this.limit,
-      offset: this.offset,
-    };
+  static from(input: ChatHistoryResponseInput): ChatHistoryResponse {
+    return new ChatHistoryResponse(input);
   }
 
-  static fromJson(json: Record<string, unknown>): ChatHistoryResponse {
-    const requireNumber = (key: string): number => {
-      const v = json[key];
-      if (typeof v !== "number") {
-        throw new Error(
-          `ChatHistoryResponse.${key} is required and must be a number`
-        );
-      }
-      return v;
-    };
-    const rawMessages = json.messages;
-    const messages: ChatMessage[] = Array.isArray(rawMessages)
-      ? (rawMessages as Record<string, unknown>[]).map((m) =>
-          ChatMessage.fromJson(m)
-        )
-      : [];
-    return new ChatHistoryResponse({
-      messages,
-      total: typeof json.total === "number" ? json.total : undefined,
-      limit: requireNumber("limit"),
-      offset: requireNumber("offset"),
-    });
+  static fromJson(json: unknown): ChatHistoryResponse {
+    return ChatHistoryResponse.from(json as ChatHistoryResponseInput);
+  }
+
+  toJson(): ChatHistoryResponseData {
+    return ChatHistoryResponseSchema.parse(this);
   }
 }