feat: hide main FAB when no terminals exist, only show with active sessions

frontend/src/App.vue

@@ -82,6 +82,9 @@ let voicePTTTimeout: number | null = null
 
 const keyboardVisible = ref(false)    // Virtual keyboard visible
 
+// Whether any terminal exists (T1+)
+const hasTerminals = computed(() => sessionState.terminalRegistry.length > 0)
+
 // Extra terminals (T2-T5) from Pinia store — fully reactive, no template ref dependency
 const extraTerminals = computed(() => {
   const reg = sessionState.terminalRegistry
@@ -107,6 +110,12 @@ function trackMouse(e: MouseEvent) {
 }
 
 function handleFabTerminalSelect(sessionId: string) {
+  const isActive = transcriptDebugRef.value?.activeTerminalSessionId === sessionId
+  if (showTranscriptDebug.value && isActive) {
+    // Already showing this terminal — close
+    showTranscriptDebug.value = false
+    return
+  }
   if (transcriptDebugRef.value) {
     transcriptDebugRef.value.switchToTerminal(sessionId)
   }
@@ -121,10 +130,21 @@ function handleFabCreateSession() {
 }
 
 function handleMainFabClick() {
-  if (transcriptDebugRef.value?.openTerminals?.length) {
-    transcriptDebugRef.value.switchToTerminal(transcriptDebugRef.value.openTerminals[0].sessionId)
+  const terminals = transcriptDebugRef.value?.openTerminals
+  if (!terminals?.length) return
+
+  const firstSessionId = terminals[0].sessionId
+  const isActive = transcriptDebugRef.value?.activeTerminalSessionId === firstSessionId
+
+  if (showTranscriptDebug.value && isActive) {
+    // Already showing terminal 1 — close
+    showTranscriptDebug.value = false
+    return
   }
-  showTranscriptDebug.value = !showTranscriptDebug.value
+
+  // Switch to terminal 1 and open
+  transcriptDebugRef.value?.switchToTerminal(firstSessionId)
+  showTranscriptDebug.value = true
 }
 
 function handleGlobalKeydown(e: KeyboardEvent) {
@@ -340,7 +360,7 @@ watch(() => route.name, (newPage) => {
         @select="handleFabTerminalSelect"
         @create-session="handleFabCreateSession"
       />
-      <div class="fab-button-area">
+      <div v-if="hasTerminals" class="fab-button-area">
         <span class="fab-bubble b1"></span>
         <span class="fab-bubble b2"></span>
         <span class="fab-bubble b3"></span>