* feat(studio): add HF/local model selection UI for GGUF export
* fix(studio):fix selector ring clipping
* fix(studio): export page trust_remote_code control and label styling
* fix(studio): accept hf_token in load_checkpoint orchestrator method
The route was passing hf_token to load_checkpoint() but the method
didn't accept it, causing a TypeError on every /api/export/load-checkpoint
request.
* fix(studio): clear HF model selection when input is edited
Previously selectedSourceModel was only cleared when the input became
empty, so editing to a different repo ID after selecting a model would
silently keep the old selection.
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Co-authored-by: Roland Tannous <rolandtannous@gravityq.ai>