feat(group-filter): 分组账号过滤控制 — require_oauth_only + require_privacy_set

为 OpenAI/Antigravity/Anthropic/Gemini 分组新增两个布尔控制字段：
- require_oauth_only: 创建/更新账号绑定分组时拒绝 apikey 类型加入
- require_privacy_set: 调度选号时跳过 privacy 未成功设置的账号并标记 error

后端：Ent schema 新增字段 + 迁移、Group CRUD 全链路透传、
      gateway_service 与 openai_account_scheduler 两套调度路径过滤
前端：创建/编辑表单 toggle 开关（OpenAI/Antigravity/Anthropic/Gemini 平台可见）

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/internal/repository/api_key_repo.go

@@ -662,6 +662,8 @@ func groupEntityToService(g *dbent.Group) *service.Group {
 		SupportedModelScopes:            g.SupportedModelScopes,
 		SortOrder:                       g.SortOrder,
 		AllowMessagesDispatch:           g.AllowMessagesDispatch,
+		RequireOAuthOnly:                g.RequireOauthOnly,
+		RequirePrivacySet:               g.RequirePrivacySet,
 		DefaultMappedModel:              g.DefaultMappedModel,
 		CreatedAt:                       g.CreatedAt,
 		UpdatedAt:                       g.UpdatedAt,

backend/internal/repository/group_repo.go

@@ -61,6 +61,8 @@ func (r *groupRepository) Create(ctx context.Context, groupIn *service.Group) er
 		SetMcpXMLInject(groupIn.MCPXMLInject).
 		SetSoraStorageQuotaBytes(groupIn.SoraStorageQuotaBytes).
 		SetAllowMessagesDispatch(groupIn.AllowMessagesDispatch).
+		SetRequireOauthOnly(groupIn.RequireOAuthOnly).
+		SetRequirePrivacySet(groupIn.RequirePrivacySet).
 		SetDefaultMappedModel(groupIn.DefaultMappedModel)
 
 	// 设置模型路由配置
@@ -130,6 +132,8 @@ func (r *groupRepository) Update(ctx context.Context, groupIn *service.Group) er
 		SetMcpXMLInject(groupIn.MCPXMLInject).
 		SetSoraStorageQuotaBytes(groupIn.SoraStorageQuotaBytes).
 		SetAllowMessagesDispatch(groupIn.AllowMessagesDispatch).
+		SetRequireOauthOnly(groupIn.RequireOAuthOnly).
+		SetRequirePrivacySet(groupIn.RequirePrivacySet).
 		SetDefaultMappedModel(groupIn.DefaultMappedModel)
 
 	// 显式处理可空字段：nil 需要 clear，非 nil 需要 set。