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/package.json

@@ -9,6 +9,11 @@
     "preview": "vite preview"
   },
   "devDependencies": {
+    "@tailwindcss/postcss": "^4.2.4",
+    "@vitejs/plugin-vue": "^6.0.6",
+    "autoprefixer": "^10.5.0",
+    "postcss": "^8.5.13",
+    "tailwindcss": "^4.2.4",
     "typescript": "~6.0.2",
     "vite": "^8.0.10"
   },
@@ -16,7 +21,9 @@
     "@headlessui/vue": "^1.7.23",
     "@vueuse/core": "^14.3.0",
     "chart.js": "^4.5.1",
+    "vue": "^3.5.33",
     "vue-chartjs": "^5.3.3",
+    "vue-i18n": "^9.14.5",
     "vue-router": "^4.6.4",
     "vue-sonner": "^2.0.9"
   }