feat(tui): add fuzzy search to model picker

- Add SearchableSelectList component with fuzzy filtering
- Integrate with /models command for quick model search
- Support up/down navigation while typing
- Uses pi-tui's fuzzyFilter for intelligent matching

src/tui/theme/theme.ts

@@ -5,6 +5,7 @@ import type {
   SettingsListTheme,
 } from "@mariozechner/pi-tui";
 import chalk from "chalk";
+import type { SearchableSelectListTheme } from "../components/searchable-select-list.js";
 
 const palette = {
   text: "#E8E3D5",
@@ -92,3 +93,14 @@ export const editorTheme: EditorTheme = {
   borderColor: (text) => fg(palette.border)(text),
   selectList: selectListTheme,
 };
+
+export const searchableSelectListTheme: SearchableSelectListTheme = {
+  selectedPrefix: (text) => fg(palette.accent)(text),
+  selectedText: (text) => chalk.bold(fg(palette.accent)(text)),
+  description: (text) => fg(palette.dim)(text),
+  scrollInfo: (text) => fg(palette.dim)(text),
+  noMatch: (text) => fg(palette.dim)(text),
+  searchPrompt: (text) => fg(palette.accentSoft)(text),
+  searchInput: (text) => fg(palette.text)(text),
+  matchHighlight: (text) => chalk.bold(fg(palette.accent)(text)),
+};