fix: use live copilot model availability

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/preload/index.ts

@@ -4,6 +4,7 @@ import { ipcChannels } from '@shared/contracts/channels';
 import type { ElectronApi } from '@shared/contracts/ipc';
 
 const api: ElectronApi = {
+  describeSidecarCapabilities: () => ipcRenderer.invoke(ipcChannels.describeSidecarCapabilities),
   loadWorkspace: () => ipcRenderer.invoke(ipcChannels.loadWorkspace),
   addProject: () => ipcRenderer.invoke(ipcChannels.addProject),
   removeProject: (projectId) => ipcRenderer.invoke(ipcChannels.removeProject, projectId),