feat: enhance profile editing with avatar support and UI adjustments

- Added AvatarPath to ProfileEditResult for user profile updates.
- Updated ProfileEditDialog to include avatar selection with a browse button.
- Increased dialog height to accommodate new avatar input fields.
- Implemented avatar file path handling in the profile edit dialog.

feat: introduce moderation features and user roles

- Added ServerRole enum to define user roles (Member, Mod, Admin, Owner).
- Extended User model to include role, mute, and ban status.
- Created ModerationController for user role assignment, kicking, banning, and muting.
- Implemented methods in IChatBroadcaster and SignalRBroadcaster for user moderation actions.
- Updated database schema with new columns for user roles and moderation states.

fix: ensure muted users cannot send messages

- Added mute status checks in ChatService to prevent message sending for muted users.
- Updated user presence and status handling to reflect role changes and moderation actions.

chore: update constants for ASCII art rendering

- Introduced AsciiArtHeightHalfBlock constant for improved ASCII art rendering.

src/EchoHub.Server.Irc/IrcBroadcaster.cs

@@ -62,6 +62,41 @@ public class IrcBroadcaster : IChatBroadcaster
         return Task.CompletedTask;
     }
 
+    public async Task SendUserKickedAsync(string channelName, string username, string? reason)
+    {
+        var reasonText = reason is not null ? $" :{reason}" : "";
+        foreach (var conn in _gateway.GetConnectionsInChannel(channelName))
+        {
+            await conn.SendAsync($":{_gateway.Options.ServerName} KICK #{channelName} {username}{reasonText}");
+        }
+    }
+
+    public async Task SendUserBannedAsync(string username, string? reason)
+    {
+        var reasonText = reason ?? "You have been banned.";
+        foreach (var conn in _gateway.GetAllConnections())
+        {
+            if (conn.Nickname == username)
+                await conn.SendAsync($":{_gateway.Options.ServerName} NOTICE {username} :You have been banned: {reasonText}");
+        }
+    }
+
+    public async Task SendMessageDeletedAsync(string channelName, Guid messageId)
+    {
+        foreach (var conn in _gateway.GetConnectionsInChannel(channelName))
+        {
+            await conn.SendAsync($":{_gateway.Options.ServerName} NOTICE {conn.Nickname ?? "*"} :Message {messageId} was deleted in #{channelName}");
+        }
+    }
+
+    public async Task SendChannelNukedAsync(string channelName)
+    {
+        foreach (var conn in _gateway.GetConnectionsInChannel(channelName))
+        {
+            await conn.SendAsync($":{_gateway.Options.ServerName} NOTICE {conn.Nickname ?? "*"} :All messages in #{channelName} have been cleared");
+        }
+    }
+
     public async Task SendErrorAsync(string connectionId, string message)
     {
         if (!connectionId.StartsWith("irc-")) return;

src/EchoHub.Server.Irc/IrcGatewayService.cs

@@ -37,6 +37,11 @@ public sealed class IrcGatewayService : BackgroundService
             .Where(c => c.IsAuthenticated && c.JoinedChannels.Contains(channelName));
     }
 
+    public IEnumerable<IrcClientConnection> GetAllConnections()
+    {
+        return _connections.Values.Where(c => c.IsAuthenticated);
+    }
+
     protected override async Task ExecuteAsync(CancellationToken stoppingToken)
     {
         await Task.Yield();