feat: complete Loki query, insights, settings and deployment workflows

Add the Loki query UI, access policies, ingress insights, alert and registry settings, and their backend APIs. Include the related Kubernetes deployment and collector updates required by the integrated application.

Validated with go test ./..., npm run build, and npm run lint.

backend/models/notify_channel.go

@@ -0,0 +1,23 @@
+package models
+
+import "time"
+
+// NotifyChannel 通知通道:一个飞书/Lark 群机器人 webhook。
+// 支持多通道对应不同告警群(如「应用告警群」「Nginx 告警群」),告警规则各自关联。
+type NotifyChannel struct {
+	ID            uint      `json:"id"`
+	Name          string    `json:"name"`
+	Webhook       string    `json:"webhook"`       // ENC: 加密存储,不外发
+	SigningSecret string    `json:"signingSecret"` // ENC: 可选签名校验
+	Enabled       bool      `json:"enabled"`
+	CreatedAt     time.Time `json:"createdAt"`
+	UpdatedAt     time.Time `json:"updatedAt"`
+}
+
+func (c *NotifyChannel) Sanitized() map[string]interface{} {
+	return map[string]interface{}{
+		"id": c.ID, "name": c.Name,
+		"hasWebhook": c.Webhook != "", "hasSecret": c.SigningSecret != "",
+		"enabled": c.Enabled, "createdAt": c.CreatedAt, "updatedAt": c.UpdatedAt,
+	}
+}