refactor(voice): integrate click-to-toggle mic into ChatInputBar; remove VoiceOverlay

frontend/src/App.vue

@@ -3,7 +3,6 @@ import { onMounted, onUnmounted, ref, watch } from "vue";
 import { useRouter } from "vue-router";
 import AppHeader from "@/components/AppHeader.vue";
 import ToastNotification from "@/components/ToastNotification.vue";
-import VoiceOverlay from "@/components/VoiceOverlay.vue";
 import { useTheme } from "@/composables/useTheme";
 import { useShortcuts } from "@/composables/useShortcuts";
 import { useAuthStore } from "@/stores/auth";
@@ -121,10 +120,6 @@ function onGlobalKeydown(e: KeyboardEvent) {
         router.push("/chat");
       }
       break;
-    case " ":
-      e.preventDefault();
-      document.dispatchEvent(new CustomEvent("voice:ptt-toggle"));
-      break;
   }
 }
 
@@ -274,10 +269,6 @@ onUnmounted(() => {
                 <kbd class="shortcut-key">Enter</kbd>
                 <span class="shortcut-desc">New line</span>
               </div>
-              <div class="shortcut-row">
-                <kbd class="shortcut-key">Space</kbd>
-                <span class="shortcut-desc">Tap to speak (voice, when enabled)</span>
-              </div>
             </div>
           </div>
         </div>
@@ -287,7 +278,6 @@ onUnmounted(() => {
   <template v-else>
     <router-view />
   </template>
-  <VoiceOverlay />
   <ToastNotification />
 </template>