This commit adds the Payment and ProxyUser entities to the database.

backend/libs/database/payment.entity.ts

@@ -0,0 +1,22 @@
+import { Entity, PrimaryGeneratedColumn, Column, ManyToOne, JoinColumn } from 'typeorm';
+import { ProxyUser } from './ProxyUser.entity';
+
+@Entity()
+export class Payment {
+    @PrimaryGeneratedColumn('uuid')
+    public id!: string;
+
+    @Column()
+    public uuidUser!: string;
+
+    @Column({ type: 'timestamptz' })
+    public payTime!: Date;
+
+    @ManyToOne(() => ProxyUser, { onDelete: 'CASCADE' }) // Assuming you want to cascade delete when a user is deleted
+    @JoinColumn({ name: 'uuidUser' })
+    user: ProxyUser;
+
+    constructor(props?: Partial<Payment>) {
+        Object.assign(this, props);
+    }
+}