fix: improve cross-device evidence, request diagnostics and prompt efficiency

apps/showcase_ui/src/app/components/agent-stream/agent-stream.component.html

@@ -509,6 +509,7 @@ limitations under the License.
   <!-- Event Logs Section -->
   <main class="stream-logs-content">
     <ng-content select="[task-summary]"></ng-content>
+    <app-llm-request-status [sessionId]="agentService.currentSessionId()" [running]="agentService.isCurrentSessionRunning()" (activeChange)="hasModelRequest.set($event)" />
     @if (agentService.isSessionContentLoading()) {
       <div class="session-loading-state" aria-live="polite">
         <span class="material-symbols-outlined spin-animation">progress_activity</span>
@@ -516,7 +517,7 @@ limitations under the License.
       </div>
     }
 
-    @if (!agentService.isSessionContentLoading() && phases().length === 0 && !showPlanningLoader() && startupWorkItems().length === 0) {
+    @if (!agentService.isSessionContentLoading() && phases().length === 0 && !showPlanningLoader() && !hasModelRequest() && startupWorkItems().length === 0) {
       <div class="empty-state">
         <div class="empty-icon"><span class="material-symbols-outlined">sensors</span></div>
         <h3>尚未选择执行记录</h3>