support PWA notification.

API/ROLAC.API/Entities/Notifications/WebPushSubscription.cs

@@ -0,0 +1,33 @@
+using ROLAC.API.Entities;
+
+namespace ROLAC.API.Entities.Notifications;
+
+/// <summary>
+/// A browser/device Web Push subscription owned by a member. Unlike <see cref="MemberChannelBinding"/>
+/// (one external id per channel), web push needs the endpoint URL plus two keys, and a member can
+/// have several — one per device/browser they enable notifications on. Targeting a member resolves
+/// all of their subscriptions.
+/// </summary>
+public class WebPushSubscription
+{
+    public int      Id         { get; set; }
+    public int      MemberId   { get; set; }
+    public Member?  Member     { get; set; }
+
+    /// <summary>The push service endpoint URL (unique per subscription).</summary>
+    public string   Endpoint   { get; set; } = null!;
+
+    /// <summary>The subscription's P-256 ECDH public key (base64url).</summary>
+    public string   P256dh     { get; set; } = null!;
+
+    /// <summary>The subscription's auth secret (base64url).</summary>
+    public string   Auth       { get; set; } = null!;
+
+    /// <summary>The originating user agent, kept for display/debugging.</summary>
+    public string?  UserAgent  { get; set; }
+
+    public DateTime CreatedAt  { get; set; }
+
+    /// <summary>Last time a push to this subscription succeeded.</summary>
+    public DateTime? LastUsedAt { get; set; }
+}