Add EchoHub as submodule and update project references paths

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "EchoHub"]
+	path = EchoHub
+	url = https://github.com/HueByte/EchoHub.git

Decho/Decho.csproj

@@ -34,7 +34,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\..\EchoHub\src\EchoHub.Client\EchoHub.Client.csproj" />
-    <ProjectReference Include="..\..\EchoHub\src\EchoHub.Core\EchoHub.Core.csproj" />
+    <ProjectReference Include="..\EchoHub\src\EchoHub.Client\EchoHub.Client.csproj" />
+    <ProjectReference Include="..\EchoHub\src\EchoHub.Core\EchoHub.Core.csproj" />
   </ItemGroup>
 </Project>

Decho/Services/ConnectionService.cs

@@ -388,7 +388,18 @@ public sealed class ConnectionService : IDisposable
     {
         if (!_connections.TryGetValue(serverUrl, out var entry))
             return null;
-        return await entry.ApiClient.DownloadBytesAsync(relativeUrl);
+        try
+        {
+            var tempPath = await entry.ApiClient.DownloadFileToTempAsync(relativeUrl, "image");
+            if (tempPath is null) return null;
+            var bytes = await File.ReadAllBytesAsync(tempPath);
+            try { File.Delete(tempPath); } catch { }
+            return bytes;
+        }
+        catch
+        {
+            return null;
+        }
     }
 
     public string? GetCurrentUsername(string serverUrl)