feat(data): add paywall payment APIs

src/data/dto/payment/payment_plan.ts

@@ -0,0 +1,36 @@
+/**
+ * 支付套餐 DTO
+ */
+import {
+  PaymentPlanSchema,
+  type PaymentPlanData,
+  type PaymentPlanInput,
+} from "@/data/schemas/payment/payment_plan";
+
+export class PaymentPlan {
+  declare readonly planId: string;
+  declare readonly planName: string;
+  declare readonly orderType: string;
+  declare readonly amountCents: number;
+  declare readonly currency: string;
+  declare readonly vipDays: number | null;
+  declare readonly dolAmount: number | null;
+
+  private constructor(input: PaymentPlanInput) {
+    const data = PaymentPlanSchema.parse(input);
+    Object.assign(this, data);
+    Object.freeze(this);
+  }
+
+  static from(input: PaymentPlanInput): PaymentPlan {
+    return new PaymentPlan(input);
+  }
+
+  static fromJson(json: unknown): PaymentPlan {
+    return PaymentPlan.from(json as PaymentPlanInput);
+  }
+
+  toJson(): PaymentPlanData {
+    return PaymentPlanSchema.parse(this);
+  }
+}