Please show models in subfolders in ComflowySpace

Right now, ComflowySpace will only show models directly in the respective model folder, like checkpoints - but it get's a real mess in no time if i keep them all in one flat directory.

Please add support for model subfolders, preferably with the ability to browse them within ComflowySpace.

Look for the model browsing and directory traversal logic in the ComflowySpace codebase, likely in a UI component or file system module. Understand how models are currently listed and where folder scanning is implemented. The goal is to modify the scanning to recursively include subfolders and update the UI to display a hierarchical view.

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