feat(app): add WGRplane web UI and backend features

- Add Vue 3 frontend with glassmorphism design (Tailwind CSS)
- Add Go backend handlers: auth, webhooks, stats, scheduler, validation
- Add i18n support (EN, ID, ZH)
- Add Swagger docs and API handlers
- Add nftables integration and plugins support
- Remove deprecated go.mod (migrated to wgrplane)

app/frontend/src/components/ActionCheckboxes.vue

@@ -0,0 +1,61 @@
+<template>
+  <div class="space-y-2">
+    <label class="block text-sm font-medium text-white/70 mb-1">Subscribed Actions</label>
+    <div class="grid grid-cols-2 gap-2">
+      <label
+        v-for="action in availableActions"
+        :key="action.value"
+        class="flex items-center gap-2 p-2 bg-white/5 rounded-lg border border-white/10 hover:border-cyan-400/50 transition-colors cursor-pointer"
+      >
+        <input
+          type="checkbox"
+          :value="action.value"
+          :checked="modelValue.includes(action.value)"
+          @change="toggleAction(action.value)"
+          class="w-4 h-4 rounded border-white/20 bg-white/5 text-cyan-500 focus:ring-cyan-500 focus:ring-offset-0"
+        />
+        <span class="text-sm text-white">{{ action.label }}</span>
+      </label>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+interface Action {
+  label: string
+  value: string
+}
+
+const props = defineProps<{
+  modelValue: string[]
+  availableActions?: Action[]
+}>()
+
+const emit = defineEmits<{
+  (e: 'update:modelValue', value: string[]): void
+}>()
+
+const defaultActions: Action[] = [
+  { label: 'Peer Connected', value: 'peer.connected' },
+  { label: 'Peer Disconnected', value: 'peer.disconnected' },
+  { label: 'Peer Added', value: 'peer.added' },
+  { label: 'Peer Removed', value: 'peer.removed' },
+  { label: 'Policy Updated', value: 'policy.updated' },
+  { label: 'Server Started', value: 'server.started' },
+  { label: 'Server Stopped', value: 'server.stopped' },
+  { label: 'Login Failed', value: 'auth.failed' }
+]
+
+const availableActions = props.availableActions || defaultActions
+
+const toggleAction = (value: string) => {
+  const current = [...props.modelValue]
+  const index = current.indexOf(value)
+  if (index === -1) {
+    current.push(value)
+  } else {
+    current.splice(index, 1)
+  }
+  emit('update:modelValue', current)
+}
+</script>