Add support for Uptime Kuma heartbeat push

Closes #186

.env-example

@@ -4,4 +4,5 @@ CLIPTOK_ANTIPHISHING_ENDPOINT=useyourimagination
 RAVY_API_TOKEN=goodluckfindingone
 CLOUDFLARED_TOKEN=ignoreifnotrelevant
 USERNAME_CHECK_ENDPOINT=https://api.example.com/username
-CLIPTALK_WEBHOOK=https://discord.com
+CLIPTALK_WEBHOOK=https://discord.com
+UPTIME_KUMA_PUSH_URL=

Events/HeartbeatEvent.cs

@@ -0,0 +1,15 @@
+namespace Cliptok.Events
+{
+    public class HeartbeatEvent
+    {
+        public static async Task OnHeartbeat(DiscordClient client, HeartbeatEventArgs e)
+        {
+            if (!string.IsNullOrEmpty(Environment.GetEnvironmentVariable("UPTIME_KUMA_PUSH_URL")))
+            {
+                var response = await Program.httpClient.GetAsync(Environment.GetEnvironmentVariable("UPTIME_KUMA_PUSH_URL") + client.Ping);
+                client.Logger.LogDebug("Heartbeat ping sent: {status} {content}", (int)response.StatusCode, await response.Content.ReadAsStringAsync());
+                return;
+            }
+        }
+    }
+}

Program.cs

@@ -151,6 +151,7 @@ static async Task Main(string[] _)
             discord.ThreadListSynced += ThreadEvents.Discord_ThreadListSynced;
             discord.ThreadMemberUpdated += ThreadEvents.Discord_ThreadMemberUpdated;
             discord.ThreadMembersUpdated += ThreadEvents.Discord_ThreadMembersUpdated;
+            discord.Heartbeated += HeartbeatEvent.OnHeartbeat;
 
             discord.GuildBanRemoved += UnbanEvent.OnUnban;