refactor: update ACP channel handling and improve error normalization

- Changed default channel from 'Desktop' to 'ACP' in AcpProcessClient and related interfaces.
- Updated tests to reflect new channel naming and added support for CLI channel overrides.
- Enhanced error handling in SessionSocketHub to normalize error responses for better clarity.
- Modified session creation and loading responses to include 'cwd' in the session object.
- Added a new test case to surface ACP prompt errors as structured protocol objects.

packages/desktop/src/renderer/components/layout/ProjectSidebar.tsx

@@ -20,6 +20,7 @@ export function ProjectSidebar({
   sessions,
   onChooseWorkspace,
   onCreateSession,
+  onFocusModelConfig,
   onSelectProject,
   onSelectSession,
 }: {
@@ -31,6 +32,7 @@ export function ProjectSidebar({
   sessions: DesktopSessionSummary[];
   onChooseWorkspace: () => void;
   onCreateSession: () => void;
+  onFocusModelConfig: () => void;
   onSelectProject: (projectId: string) => void;
   onSelectSession: (sessionId: string) => void;
 }) {
@@ -50,6 +52,24 @@ export function ProjectSidebar({
         </div>
       </div>
 
+      <section className="sidebar-section quick-actions">
+        <button
+          className="primary-button"
+          disabled={loadState.state !== 'ready' || !activeProject}
+          type="button"
+          onClick={onCreateSession}
+        >
+          New Thread
+        </button>
+        <button
+          className="secondary-button"
+          type="button"
+          onClick={onFocusModelConfig}
+        >
+          Model Config
+        </button>
+      </section>
+
       <section className="sidebar-section">
         <h2>Projects</h2>
         <div className="workspace-path">
@@ -71,14 +91,6 @@ export function ProjectSidebar({
 
       <section className="sidebar-section sidebar-section-fill">
         <h2>Threads</h2>
-        <button
-          className="primary-button"
-          disabled={loadState.state !== 'ready' || !activeProject}
-          type="button"
-          onClick={onCreateSession}
-        >
-          New Thread
-        </button>
         <ThreadList
           activeSessionId={activeSessionId}
           sessions={sessions}