feat(group): 添加 MCP XML 注入开关

- Group 新增 mcp_xml_inject 字段，控制 Antigravity 平台的 MCP XML 协议注入
- 默认启用，可在分组设置中关闭
- 修复 GetByKeyForAuth 遗漏查询 mcp_xml_inject 字段导致认证缓存值始终为 false 的问题

backend/ent/group/where.go

@@ -160,6 +160,11 @@ func ModelRoutingEnabled(v bool) predicate.Group {
 	return predicate.Group(sql.FieldEQ(FieldModelRoutingEnabled, v))
 }
 
+// McpXMLInject applies equality check predicate on the "mcp_xml_inject" field. It's identical to McpXMLInjectEQ.
+func McpXMLInject(v bool) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldMcpXMLInject, v))
+}
+
 // CreatedAtEQ applies the EQ predicate on the "created_at" field.
 func CreatedAtEQ(v time.Time) predicate.Group {
 	return predicate.Group(sql.FieldEQ(FieldCreatedAt, v))
@@ -1145,6 +1150,16 @@ func ModelRoutingEnabledNEQ(v bool) predicate.Group {
 	return predicate.Group(sql.FieldNEQ(FieldModelRoutingEnabled, v))
 }
 
+// McpXMLInjectEQ applies the EQ predicate on the "mcp_xml_inject" field.
+func McpXMLInjectEQ(v bool) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldMcpXMLInject, v))
+}
+
+// McpXMLInjectNEQ applies the NEQ predicate on the "mcp_xml_inject" field.
+func McpXMLInjectNEQ(v bool) predicate.Group {
+	return predicate.Group(sql.FieldNEQ(FieldMcpXMLInject, v))
+}
+
 // HasAPIKeys applies the HasEdge predicate on the "api_keys" edge.
 func HasAPIKeys() predicate.Group {
 	return predicate.Group(func(s *sql.Selector) {