feat: global right-click control + topic tree context menu

- UseContextMenu composable: global right-click prevention
  - PROD: prevent default browser context menu everywhere
  - DEV: allow native context menu for debugging
- ContextMenu component: reusable custom right-click menu
- TopicTree: right-click nodes for copy topic / subscribe / unsubscribe / filter
  - Copy topic to clipboard
  - Subscribe with QoS 0/1/2
  - Unsubscribe with confirmation
  - Filter by topic

src/App.vue

@@ -1,5 +1,8 @@
 <script setup lang="ts">
-import AppLayout from "./components/AppLayout.vue";
+import { useContextMenuController } from "./composables/useContextMenu"
+import AppLayout from "./components/AppLayout.vue"
+
+useContextMenuController()
 </script>
 
 <template>

src/components/common/ContextMenu.vue

@@ -0,0 +1,134 @@
+<script setup lang="ts">
+import { ref, onMounted, onUnmounted } from 'vue'
+
+export interface ContextMenuItem {
+  label: string
+  icon?: string
+  danger?: boolean
+  disabled?: boolean
+  divider?: boolean
+  action: () => void
+}
+
+const props = defineProps<{
+  items: ContextMenuItem[]
+}>()
+
+const visible = ref(false)
+const x = ref(0)
+const y = ref(0)
+let targetEl: HTMLElement | null = null
+let cleanup: (() => void) | null = null
+
+function show(ev: MouseEvent, el: HTMLElement) {
+  x.value = ev.clientX
+  y.value = ev.clientY
+  targetEl = el
+  visible.value = true
+}
+
+function hide() {
+  visible.value = false
+  targetEl = null
+}
+
+function handleAction(item: ContextMenuItem) {
+  if (item.disabled) return
+  hide()
+  item.action()
+}
+
+function onClickOutside(e: MouseEvent) {
+  const menu = document.querySelector('.context-menu')
+  if (menu && !menu.contains(e.target as Node)) {
+    hide()
+  }
+}
+
+onMounted(() => {
+  document.addEventListener('click', onClickOutside)
+})
+
+onUnmounted(() => {
+  document.removeEventListener('click', onClickOutside)
+  if (cleanup) cleanup()
+})
+
+defineExpose({ show, hide })
+</script>
+
+<template>
+  <Teleport to="body">
+    <div
+      v-if="visible"
+      class="context-menu"
+      :style="{ left: x + 'px', top: y + 'px' }"
+    >
+      <div
+        v-for="(item, idx) in items"
+        :key="idx"
+        :class="['ctx-item', { danger: item.danger, disabled: item.disabled, divider: item.divider }]"
+        @click="handleAction(item)"
+      >
+        <span v-if="item.icon" class="ctx-icon">{{ item.icon }}</span>
+        <span class="ctx-label">{{ item.label }}</span>
+      </div>
+    </div>
+  </Teleport>
+</template>
+
+<style scoped>
+.context-menu {
+  position: fixed;
+  z-index: 9999;
+  min-width: 140px;
+  background: var(--el-bg-color);
+  border: 1px solid var(--el-border-color);
+  border-radius: 6px;
+  padding: 4px;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+  font-size: 12px;
+}
+.ctx-item {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 6px 10px;
+  border-radius: 4px;
+  cursor: pointer;
+  color: var(--el-text-color-regular);
+  transition: background 0.1s;
+  user-select: none;
+}
+.ctx-item:hover {
+  background: var(--el-fill-color-light);
+}
+.ctx-item.danger {
+  color: var(--el-color-danger);
+}
+.ctx-item.danger:hover {
+  background: var(--el-color-danger-light-9);
+}
+.ctx-item.disabled {
+  opacity: 0.4;
+  cursor: not-allowed;
+}
+.ctx-item.disabled:hover {
+  background: transparent;
+}
+.ctx-item.divider {
+  border-top: 1px solid var(--el-border-color-light);
+  margin-top: 2px;
+  padding-top: 8px;
+}
+.ctx-icon {
+  font-size: 14px;
+  width: 18px;
+  text-align: center;
+  flex-shrink: 0;
+}
+.ctx-label {
+  flex: 1;
+  white-space: nowrap;
+}
+</style>

src/components/dashboard/TopicTree.vue

@@ -5,6 +5,8 @@ import type { MqttMessage } from '../../types/mqtt'
 import type { Subscription } from '../../types/mqtt'
 import { useSubscriptions } from '../../stores/useSubscriptions'
 import { mqttSubscribe, mqttUnsubscribe } from '../../stores/useMqttBridge'
+import ContextMenu from '../common/ContextMenu.vue'
+import type { ContextMenuItem } from '../common/ContextMenu.vue'
 
 interface TopicNode {
   id: string
@@ -30,6 +32,74 @@ const emit = defineEmits<{
 
 const { addSubscription, removeSubscription, getSubscriptionsByConnection } = useSubscriptions()
 
+const ctxMenu = ref<InstanceType<typeof ContextMenu>>()
+const ctxTopic = ref('')
+const ctxNode = ref<TopicNode | null>(null)
+const ctxMenuItems = ref<ContextMenuItem[]>([])
+
+function handleContextMenu(ev: MouseEvent, node: TopicNode) {
+  ev.preventDefault()
+  ctxTopic.value = node.fullPath
+  ctxNode.value = node
+  const items: ContextMenuItem[] = []
+
+  // Copy topic
+  items.push({
+    label: '复制主题',
+    icon: '📋',
+    action: () => navigator.clipboard.writeText(node.fullPath),
+  })
+
+  // Subscribe / Unsubscribe
+  if (node.isSubscribed) {
+    items.push({
+      label: `取消订阅 (QoS ${node.subscriptionQos})`,
+      icon: '❌',
+      danger: true,
+      action: () => handleUnsubscribe(node.fullPath),
+    })
+  } else if (props.connected) {
+    items.push({
+      label: '订阅 (QoS 0)',
+      icon: '➕',
+      action: () => handleSubscribeTopic(node.fullPath, 0),
+    })
+    items.push({
+      label: '订阅 (QoS 1)',
+      icon: '➕',
+      action: () => handleSubscribeTopic(node.fullPath, 1),
+    })
+    items.push({
+      label: '订阅 (QoS 2)',
+      icon: '➕',
+      action: () => handleSubscribeTopic(node.fullPath, 2),
+    })
+  }
+
+  items.push({ label: '', icon: '', divider: true, action: () => {} })
+
+  // Select topic (filter messages)
+  items.push({
+    label: '筛选此主题',
+    icon: '🔍',
+    action: () => emit('select', node.fullPath),
+  })
+
+  ctxMenuItems.value = items
+  ctxMenu.value?.show(ev, ev.target as HTMLElement)
+}
+
+async function handleSubscribeTopic(topic: string, qos: number) {
+  if (!props.connectionId) return
+  try {
+    await mqttSubscribe({ connection_id: props.connectionId, topic, qos })
+    addSubscription(props.connectionId, topic, qos)
+    ElMessage.success(`已订阅: ${topic} (QoS ${qos})`)
+  } catch (e: unknown) {
+    ElMessage.error(`订阅失败: ${e instanceof Error ? e.message : String(e)}`)
+  }
+}
+
 const subscribeInput = ref('')
 const subscribeQos = ref<0 | 1 | 2>(0)
 const subscribing = ref(false)
@@ -194,7 +264,7 @@ function getNodeClass(node: TopicNode): string {
 
     <div class="tree-list">
       <template v-for="node in treeData" :key="node.id">
-        <div :class="['tree-node', getNodeClass(node)]" @click="handleNodeClick(node)">
+        <div :class="['tree-node', getNodeClass(node)]" @click="handleNodeClick(node)" @contextmenu.prevent="handleContextMenu($event, node)">
           <span class="node-icon">{{ getNodeIcon(node) }}</span>
           <span class="node-label">{{ node.label }}</span>
           <span class="node-count">{{ node.count }}</span>
@@ -202,7 +272,7 @@ function getNodeClass(node: TopicNode): string {
         </div>
         <div v-if="node.children.length > 0" class="children-group">
           <template v-for="child in node.children" :key="child.id">
-            <div :class="['tree-node child', getNodeClass(child)]" @click="handleNodeClick(child)">
+            <div :class="['tree-node child', getNodeClass(child)]" @click="handleNodeClick(child)" @contextmenu.prevent="handleContextMenu($event, child)">
               <span class="node-icon">{{ getNodeIcon(child) }}</span>
               <span class="node-label">{{ child.label }}</span>
               <span class="node-count">{{ child.count }}</span>
@@ -214,6 +284,7 @@ function getNodeClass(node: TopicNode): string {
                 :key="gc.id"
                 :class="['tree-node child', { selected: gc.fullPath === selectedTopic, subscribed: gc.isSubscribed }]"
                 @click="handleNodeClick(gc)"
+                @contextmenu.prevent="handleContextMenu($event, gc)"
               >
                 <span class="node-icon">{{ getNodeIcon(gc) }}</span>
                 <span class="node-label">{{ gc.label }}</span>
@@ -225,6 +296,8 @@ function getNodeClass(node: TopicNode): string {
         </div>
       </template>
     </div>
+
+    <ContextMenu ref="ctxMenu" :items="ctxMenuItems" />
   </div>
 </template>
 

src/composables/useContextMenu.ts

@@ -0,0 +1,41 @@
+import { onMounted, onUnmounted } from 'vue'
+
+const contextMenuHandlers = new Set<(e: MouseEvent) => void>()
+
+/**
+ * Register a custom right-click handler.
+ * The handler should call `e.preventDefault()` if it handles the event.
+ */
+export function registerContextMenu(handler: (e: MouseEvent) => void) {
+  contextMenuHandlers.add(handler)
+}
+
+export function unregisterContextMenu(handler: (e: MouseEvent) => void) {
+  contextMenuHandlers.delete(handler)
+}
+
+/**
+ * Global context menu controller.
+ * In production: prevents default browser context menu everywhere.
+ * In debug (dev mode): allows native context menu.
+ * Custom handlers registered via registerContextMenu take priority.
+ */
+export function useContextMenuController() {
+  function onContextMenu(e: MouseEvent) {
+    for (const handler of contextMenuHandlers) {
+      handler(e)
+      if (e.defaultPrevented) return
+    }
+    if (import.meta.env.PROD) {
+      e.preventDefault()
+    }
+  }
+
+  onMounted(() => {
+    document.addEventListener('contextmenu', onContextMenu)
+  })
+
+  onUnmounted(() => {
+    document.removeEventListener('contextmenu', onContextMenu)
+  })
+}