Files written to the temp directory (e.g. GLSLShader_output_00004_.png)
caused a ValueError in get_asset_category_and_relative_path when
--enable-assets was active, because the temp directory was not a
recognized asset root.
Add 'temp' as a category alongside input/output/models so temp outputs
can be registered as assets.
Amp-Thread-ID: https://ampcode.com/threads/T-019d2800-6944-7039-b2c4-53f809bc7f4f
Co-authored-by: Amp <amp@ampcode.com>
