feat: 网络双线图+告警联系人/联系组+Agent v2.0.0 + 一键报警阈值

- HostMonitor: 网络改为双线图 rx/tx 网卡带宽吞吐(双Area线), 移除单rx图
- Agent: 默认版本号从 dev 改为 v2.0.0, 重建二进制 5.2MB
- 告警中心: 新增报警联系人/报警联系组 Tab, ContactDialog/ContactGroupDialog
- 后端: AlertContact/AlertContactGroup 模型+CRUD, monitor_alert_contacts/groups 表
- 路由: /alerts/contacts + /alerts/contact-groups 8个REST端点
- 一键报警: 更新描述为6条规则(含TCP+进程), 切换到 /alerts/quick-setup
- 测试规则: 内存>10% 触发告警已创建, 飞书通知验证通过

backend/internal/models/alert.go

@@ -395,6 +395,79 @@ type AcknowledgeAlertRequest struct {
 	Message string `json:"message"`
 }
 
+// ============================================
+// AlertContact 报警联系人
+// ============================================
+
+type AlertContact struct {
+	ID        uint           `gorm:"primaryKey;autoIncrement;comment:主键ID" json:"id"`
+	Name      string         `gorm:"type:varchar(128);not null;comment:联系人姓名" json:"name"`
+	Phone     string         `gorm:"type:varchar(32);comment:手机号" json:"phone,omitempty"`
+	Email     string         `gorm:"type:varchar(128);comment:邮箱" json:"email,omitempty"`
+	Dingtalk  string         `gorm:"type:varchar(256);comment:钉钉webhook地址" json:"dingtalk,omitempty"`
+	Feishu    string         `gorm:"type:varchar(256);comment:飞书webhook地址" json:"feishu,omitempty"`
+	Wechat    string         `gorm:"type:varchar(256);comment:企业微信webhook地址" json:"wechat,omitempty"`
+	CreatedAt time.Time      `gorm:"not null;comment:创建时间" json:"created_at"`
+	UpdatedAt time.Time      `gorm:"not null;comment:更新时间" json:"updated_at"`
+	DeletedAt gorm.DeletedAt `gorm:"index;comment:删除时间" json:"deleted_at,omitempty"`
+}
+
+func (AlertContact) TableName() string {
+	return "monitor_alert_contacts"
+}
+
+// ============================================
+// AlertContactGroup 报警联系组
+// ============================================
+
+type AlertContactGroup struct {
+	ID         uint           `gorm:"primaryKey;autoIncrement;comment:主键ID" json:"id"`
+	GroupName  string         `gorm:"type:varchar(128);not null;comment:组名称" json:"group_name"`
+	Notes      string         `gorm:"type:varchar(500);comment:备注" json:"notes,omitempty"`
+	ContactIDs string         `gorm:"type:text;comment:联系人ID列表JSON" json:"contact_ids,omitempty"`
+	CreatedAt  time.Time      `gorm:"not null;comment:创建时间" json:"created_at"`
+	UpdatedAt  time.Time      `gorm:"not null;comment:更新时间" json:"updated_at"`
+	DeletedAt  gorm.DeletedAt `gorm:"index;comment:删除时间" json:"deleted_at,omitempty"`
+}
+
+func (AlertContactGroup) TableName() string {
+	return "monitor_alert_contact_groups"
+}
+
+// CreateContactRequest 创建联系人请求
+type CreateContactRequest struct {
+	Name     string `json:"name" binding:"required"`
+	Phone    string `json:"phone,omitempty"`
+	Email    string `json:"email,omitempty"`
+	Dingtalk string `json:"dingtalk,omitempty"`
+	Feishu   string `json:"feishu,omitempty"`
+	Wechat   string `json:"wechat,omitempty"`
+}
+
+// UpdateContactRequest 更新联系人请求
+type UpdateContactRequest struct {
+	Name     string `json:"name,omitempty"`
+	Phone    string `json:"phone,omitempty"`
+	Email    string `json:"email,omitempty"`
+	Dingtalk string `json:"dingtalk,omitempty"`
+	Feishu   string `json:"feishu,omitempty"`
+	Wechat   string `json:"wechat,omitempty"`
+}
+
+// CreateContactGroupRequest 创建联系组请求
+type CreateContactGroupRequest struct {
+	GroupName  string `json:"group_name" binding:"required"`
+	Notes      string `json:"notes,omitempty"`
+	ContactIDs []uint `json:"contact_ids"`
+}
+
+// UpdateContactGroupRequest 更新联系组请求
+type UpdateContactGroupRequest struct {
+	GroupName  string `json:"group_name,omitempty"`
+	Notes      string `json:"notes,omitempty"`
+	ContactIDs []uint `json:"contact_ids,omitempty"`
+}
+
 // CreateNotifyChannelRequest 创建通知渠道请求
 type CreateNotifyChannelRequest struct {
 	Name   string `json:"name" binding:"required"`
@@ -426,7 +499,7 @@ type FeishuCardContent struct {
 	Title   string                `json:"title"`
 	Content [][]FeishuCardElement `json:"content"`
 }
-
+// FeishuCardElement 飞书卡片元素
 type FeishuCardElement struct {
 	Tag  string `json:"tag"`
 	Text string `json:"text,omitempty"`