fix: Skip auto-focus on mobile to prevent keyboard from opening on prompt bar show

frontend/src/components/agent/ChatInput.vue

@@ -34,8 +34,10 @@ function focus() {
   inputEl.value?.focus()
 }
 
+const isMobile = () => window.innerWidth < 480
+
 watch(() => props.autofocus, async (v) => {
-  if (v) {
+  if (v && !isMobile()) {
     await nextTick()
     focus()
   }

frontend/src/components/agent/PromptBar.vue

@@ -651,7 +651,7 @@ watch(() => props.visible, async (v) => {
     await nextTick()
     if (props.startRecording) {
       handleMic()
-    } else {
+    } else if (window.innerWidth >= 480) {
       chatInputEl.value?.focus()
     }
   } else {