fix(tui): add missing `theme_list` keybind (#6779)

Co-authored-by: Adam Spiers <[email protected]>

packages/opencode/src/cli/cmd/tui/app.tsx

@@ -412,6 +412,7 @@ function App() {
     {
       title: "Switch theme",
       value: "theme.switch",
+      keybind: "theme_list",
       onSelect: () => {
         dialog.replace(() => <DialogThemeList />)
       },