* fix: support large proxy model endpoint refresh
Large OpenAI-compatible proxy endpoints can expose hundreds of models and make /v1/models slow. Treating those endpoints like local model servers caused model picker opens and background probes to repeatedly hit /models, producing timeouts and making otherwise usable endpoints appear offline.
Make model endpoint discovery cached-first for normal UI usage, add explicit proxy/API classification and refresh policy fields, exclude proxy/API endpoints from aggressive local probing, and preserve cached models when refresh fails.
Manual Test/Add/Refresh actions still fetch the full model list with longer timeouts so users can intentionally import large proxy model lists without blocking normal model picker usage.
* fix: preserve endpoint ping status semantics
- Turn the "/setup" text on the welcome screen and fallback state into a clickable link that automatically runs the setup command.
- Add an interactive down-arrow "Use in Chat" button next to copy button on typewriter-generated setup code blocks.
- Programmatically trim the "..." placeholder when inserting API keys, focusing the cursor right after "sk-".
- Implement click-delegation for supported provider spans and raw code elements inside the setup guide to instantly pre-populate the input bar.
