## Motivation
Fixes#1648. Users adding custom models from HuggingFace got no clear
feedback that the model was successfully added — the model didn't appear
prominently in the list. Additionally, searches were limited to
`mlx-community` models with no fallback.
## Changes
- **Success feedback**: After adding a custom model, a toast
notification appears, the view auto-switches to "All Models", and the
newly added model is scrolled into view with a green highlight that
fades over 4 seconds.
- **HuggingFace search fallback**: The `/models/search` endpoint now
searches `mlx-community` first; if no results are found, it falls back
to searching all of HuggingFace.
- **Inline HF results**: When the main search bar finds no local
matches, HuggingFace search results appear inline with "+ Add" buttons
and a "See all results on Hub" link.
- **Full repo ID for non-mlx models**: Non-mlx-community models now
display the full repo ID (e.g., `meta-llama/Llama-3.1-8B`) instead of
just the short name.
## Why It Works
The toast + scroll + highlight gives immediate, unambiguous feedback
that the model was added and where it lives in the list. The HF search
fallback broadens discoverability while still prioritising mlx-community
models. Inline results in the main search bar mean users don't need to
navigate to the HF tab to discover new models.
## Test Plan
### Manual Testing
- Open model picker → HuggingFace Hub tab → search for a model → click
"+ Add"
- Verify: toast appears, view switches to All Models, model highlighted
with green glow
- Search for a term with no mlx-community results → verify fallback to
full HF search
- Non-mlx-community results show full repo ID (e.g., `org/model-name`)
- On All Models tab, search for a model not in the local list → verify
"From HuggingFace" section appears
### Automated Testing
- Existing tests cover the model catalog and API; no new automated tests
needed for UI behaviour changes
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Co-authored-by: Evan <[email protected]>
