feat(bet-provider): 添加开注商管理功能，包括增删改查接口及相关模型和迁移文件

app/Models/BetProvider.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+/** 开注商目录 {@see bet_providers} */
+final class BetProvider extends Model
+{
+    public const DEFAULT_CODE = 'SG';
+
+    protected $fillable = [
+        'code',
+        'name',
+        'is_enabled',
+        'sort_order',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'is_enabled' => 'boolean',
+            'sort_order' => 'integer',
+        ];
+    }
+}