Fix chat bulk delete URL resolution

server/QMax.Api/Infrastructure/Max/IMaxBridgeClient.cs

@@ -9,6 +9,7 @@ public interface IMaxBridgeClient
     Task<IReadOnlyList<MaxChatUpdate>> FetchUpdatesAsync(CancellationToken cancellationToken);
     Task<MaxChatUpdate?> FetchChatHistoryAsync(string externalChatId, string? chatUrl, CancellationToken cancellationToken);
     Task<MaxChatPresence?> FetchChatPresenceAsync(string externalChatId, string? chatUrl, CancellationToken cancellationToken);
+    Task<MaxChatUrlResult> ResolveChatUrlAsync(string externalChatId, CancellationToken cancellationToken);
     Task<MaxActionResult> ClearChatHistoryAsync(string externalChatId, string? chatUrl, CancellationToken cancellationToken);
     Task<MaxActionResult> DeleteChatAsync(string externalChatId, string? chatUrl, CancellationToken cancellationToken);
     Task<MaxSendResult> SendTextAsync(string externalChatId, string? chatUrl, string text, CancellationToken cancellationToken);

server/QMax.Api/Infrastructure/Max/MaxBridgeModels.cs

@@ -53,6 +53,8 @@ public sealed record MaxSendResult(bool Success, string? ExternalMessageId, stri
 
 public sealed record MaxActionResult(bool Success, string? Error);
 
+public sealed record MaxChatUrlResult(bool Success, string? ChatUrl, string? Error);
+
 public sealed record MaxMediaDownload(
     Stream Stream,
     string ContentType,

server/QMax.Api/Infrastructure/Max/MockMaxBridgeClient.cs

@@ -56,6 +56,11 @@ public sealed class MockMaxBridgeClient : IMaxBridgeClient
         return Task.FromResult<MaxChatPresence?>(new MaxChatPresence(false, null, DateTimeOffset.UtcNow));
     }
 
+    public Task<MaxChatUrlResult> ResolveChatUrlAsync(string externalChatId, CancellationToken cancellationToken)
+    {
+        return Task.FromResult(new MaxChatUrlResult(true, MockChatUrl(externalChatId), null));
+    }
+
     public Task<MaxActionResult> ClearChatHistoryAsync(string externalChatId, string? chatUrl, CancellationToken cancellationToken)
     {
         return Task.FromResult(new MaxActionResult(true, null));

server/QMax.Api/Infrastructure/Max/WorkerMaxBridgeClient.cs

@@ -53,6 +53,12 @@ public sealed class WorkerMaxBridgeClient(
         return await SendAsync<MaxChatPresence>(HttpMethod.Post, "/chat/presence", new { externalChatId, chatUrl }, cancellationToken);
     }
 
+    public async Task<MaxChatUrlResult> ResolveChatUrlAsync(string externalChatId, CancellationToken cancellationToken)
+    {
+        return await SendAsync<MaxChatUrlResult>(HttpMethod.Post, "/chat/resolve-url", new { externalChatId }, cancellationToken)
+            ?? new MaxChatUrlResult(false, null, "Worker returned an empty chat URL result.");
+    }
+
     public async Task<MaxActionResult> ClearChatHistoryAsync(string externalChatId, string? chatUrl, CancellationToken cancellationToken)
     {
         return await SendAsync<MaxActionResult>(