feat(#116): update command hooks for synchronous group response

Add CommandGroupResponse and ConfigUpdateResponse types. Switch
useSendGroupCommand and useSendRouteCommand from openapi-fetch to authFetch
returning CommandGroupResponse. Update useUpdateApplicationConfig to return
ConfigUpdateResponse and fix all consumer onSuccess callbacks to access
saved.config.version instead of saved.version.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/pages/AgentHealth/AgentHealth.tsx

@@ -145,7 +145,7 @@ export default function AgentHealth() {
       onSuccess: (saved) => {
         setConfigEditing(false);
         setConfigDraft({});
-        toast({ title: 'Config updated', description: `${appId} (v${saved.version})`, variant: 'success' });
+        toast({ title: 'Config updated', description: `${appId} (v${saved.config.version})`, variant: 'success' });
       },
       onError: () => {
         toast({ title: 'Config update failed', variant: 'error' });