feat: 手动充值、邀请码注册与后台管理增强

新增玩家手动充值全流程（收款方式配置、充值下单/审核、钱包上分），
支持邀请码注册、邀请历史与专属返水率；完善后台代理/玩家管理与响应式操作栏，
并补充前台注册、充值页及多语言错误码。

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/api/src/domains/identity/auth.dto.ts

@@ -1,4 +1,4 @@
-import { IsString, MinLength } from 'class-validator';
+import { IsString, MinLength, IsOptional, IsNumber } from 'class-validator';
 import { ApiProperty } from '@nestjs/swagger';
 
 export class LoginDto {
@@ -12,6 +12,27 @@ export class LoginDto {
   password!: string;
 }
 
+export class RegisterDto {
+  @ApiProperty()
+  @IsString()
+  username!: string;
+
+  @ApiProperty()
+  @IsString()
+  @MinLength(8)
+  password!: string;
+
+  @ApiProperty({ required: false })
+  @IsOptional()
+  @IsString()
+  inviteCode?: string;
+
+  @ApiProperty({ required: false })
+  @IsOptional()
+  @IsString()
+  locale?: string;
+}
+
 export class ChangePasswordDto {
   @ApiProperty()
   @IsString()
@@ -22,3 +43,10 @@ export class ChangePasswordDto {
   @MinLength(8)
   newPassword!: string;
 }
+
+export class GenerateInviteDto {
+  @ApiProperty({ required: false, description: 'Decimal cashback rate, e.g. 0.01 = 1%. Admin only.' })
+  @IsOptional()
+  @IsNumber()
+  cashbackRate?: number;
+}