Fix kohya_ss install

CHANGELOG.md

@@ -33,6 +33,7 @@ and this project adheres to [Semantic Versioning 2.0](https://semver.org/spec/v2
 - Fixed [#502](https://github.com/LykosAI/StabilityMatrix/issues/502) - missing launch options for Forge
 - Fixed [#500](https://github.com/LykosAI/StabilityMatrix/issues/500) - missing output images in Forge when using output sharing
 - Fixed [#490](https://github.com/LykosAI/StabilityMatrix/issues/490) - `mpmath has no attribute 'rational'` error on macOS
+- Fixed kohya_ss packages with v23.0.x failing to install due to missing 'packaging' dependency
 - Fixed incorrect progress text when deleting a checkpoint from the Checkpoints page
 - Fixed incorrect icon colors on macOS
 

StabilityMatrix.Core/Models/Packages/KohyaSs.cs

@@ -122,6 +122,9 @@ public class KohyaSs(
         venvRunner.WorkingDirectory = installLocation;
         await venvRunner.Setup(true, onConsoleOutput).ConfigureAwait(false);
 
+        // Extra dep needed before running setup since v23.0.x
+        await venvRunner.PipInstall("packaging").ConfigureAwait(false);
+
         if (Compat.IsWindows)
         {
             var setupSmPath = Path.Combine(installLocation, "setup", "setup_sm.py");