feat: 通知系统(notifications表+CRUD接口+管理员接口)

src/models.rs

@@ -401,3 +401,21 @@ pub struct PaymentOrder {
     pub expires_at: Option<chrono::DateTime<chrono::Utc>>,
     pub created_at: chrono::DateTime<chrono::Utc>,
 }
+
+// ===== 通知系统 =====
+
+#[derive(Debug, Serialize, FromRow)]
+pub struct Notification {
+    pub id: i32,
+    pub scope: String,
+    pub user_id: Option<i32>,
+    #[sqlx(rename = "type")]
+    pub type_: String,
+    pub title: String,
+    pub content: Option<String>,
+    pub priority: String,
+    pub link: Option<String>,
+    pub is_read: bool,
+    pub created_at: chrono::DateTime<chrono::Utc>,
+    pub expires_at: Option<chrono::DateTime<chrono::Utc>>,
+}