Replace the flat dump of every model in the chat-input picker with a
quick-switch. Opening the picker now shows a search box, an auto-tracked
Recent list (last 5 picks), and a manual Favorites list instead of every
available model crammed into a 280px dropdown. With large catalogs
(e.g. OpenRouter's 350+ models) this was unusable as both a quick-switch
and a browser.
- Recent: each pick is recorded most-recent-first (capped at 5) under a
new odysseus-model-recent key, so the next open has it one click away.
- Favorites: an inline star on every row toggles favorite state and
writes the existing odysseus-model-favorites key, so the sidebar Models
section stays in sync. The star toggles only — it never picks the model.
- Search filters a flat list across the whole catalog; favorited rows
keep their filled star while filtered.
- Small catalogs (<=12 models) still list everything in browse mode so
tiny installs aren't forced to search for a model.
- Touch friendly: stars are always visible (no hover-reveal) and tap
targets grow on narrow screens.
No changes to sidebar visibility defaults.
Closes#399
