feat: Add persistent terminal with floating UI

- Server keeps PTY sessions alive on client disconnect
- Output buffer replays history on reconnect
- FloatingTerminal component accessible from any page
- Responsive: floating window on desktop, fullscreen on mobile
- macOS-style header with traffic light buttons

frontend/src/App.vue

@@ -1,16 +1,18 @@
 <script setup lang="ts">
-import { onMounted, watch } from 'vue'
+import { ref, onMounted, watch } from 'vue'
 import { RouterView, useRoute, useRouter } from 'vue-router'
 import StatusBar from './components/StatusBar.vue'
 import Toolbar from './components/Toolbar.vue'
 import ComponentsDropdown from './components/ComponentsDropdown.vue'
+import FloatingTerminal from './components/FloatingTerminal.vue'
 import { initWebMCP } from './services/webmcp'
 import { initToolRegistry, activatePageTools, initToolsOnRefresh } from './services/toolRegistry'
 
 const route = useRoute()
 const router = useRouter()
+const showTerminal = ref(false)
 
-type PageName = 'home' | 'canvas' | 'components' | 'themes' | 'projects' | 'project-canvas' | 'database' | 'source'
+type PageName = 'home' | 'canvas' | 'components' | 'themes' | 'projects' | 'project-canvas' | 'database' | 'source' | 'terminal'
 
 onMounted(async () => {
   // Initialize WebMCP connection
@@ -49,6 +51,26 @@ watch(() => route.name, (newPage) => {
         </Transition>
       </RouterView>
     </main>
+
+    <!-- Floating Terminal Toggle Button -->
+    <button
+      class="terminal-fab"
+      :class="{ active: showTerminal }"
+      @click="showTerminal = !showTerminal"
+      title="Toggle Terminal"
+    >
+      <svg v-if="!showTerminal" xmlns="http://www.w3.org/2000/svg" width="22" height="22" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+        <polyline points="4 17 10 11 4 5"></polyline>
+        <line x1="12" y1="19" x2="20" y2="19"></line>
+      </svg>
+      <svg v-else xmlns="http://www.w3.org/2000/svg" width="22" height="22" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+        <line x1="18" y1="6" x2="6" y2="18"></line>
+        <line x1="6" y1="6" x2="18" y2="18"></line>
+      </svg>
+    </button>
+
+    <!-- Floating Terminal -->
+    <FloatingTerminal v-model="showTerminal" />
   </div>
 </template>
 
@@ -103,4 +125,53 @@ watch(() => route.name, (newPage) => {
   opacity: 0;
   transform: translateX(-20px);
 }
+
+/* Terminal FAB */
+.terminal-fab {
+  position: fixed;
+  bottom: 20px;
+  right: 20px;
+  width: 56px;
+  height: 56px;
+  border-radius: 16px;
+  background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
+  color: white;
+  border: none;
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  box-shadow: 0 8px 24px rgba(99, 102, 241, 0.4);
+  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
+  z-index: 9998;
+}
+
+.terminal-fab:hover {
+  transform: scale(1.05);
+  box-shadow: 0 12px 32px rgba(99, 102, 241, 0.5);
+}
+
+.terminal-fab.active {
+  background: #ef4444;
+  box-shadow: 0 8px 24px rgba(239, 68, 68, 0.4);
+  transform: rotate(90deg);
+}
+
+.terminal-fab.active:hover {
+  box-shadow: 0 12px 32px rgba(239, 68, 68, 0.5);
+}
+
+@media (max-width: 768px) {
+  .terminal-fab {
+    bottom: 16px;
+    right: 16px;
+    width: 52px;
+    height: 52px;
+  }
+
+  .terminal-fab.active {
+    opacity: 0;
+    pointer-events: none;
+  }
+}
 </style>