refactor(forms): Migrate Forms.vue to Vue 3 Composition API

- Converted component to use Vue 3's Composition API with setup()
- Removed duplicate function declarations and fixed syntax issues
- Updated lifecycle hooks to use onMounted/onUnmounted
- Fixed reactivity using ref and computed
- Cleaned up event handling and component structure
- Ensured compatibility with Vue 3 and Nextcloud ecosystem

Author: nfebe

package.json

@@ -52,19 +52,22 @@
     "vuedraggable": "^2.24.3"
   },
   "devDependencies": {
-    "@mdi/js": "^7.4.47",
-    "@mdi/svg": "^7.4.47",
     "@nextcloud/browserslist-config": "^3.0.1",
     "@nextcloud/e2e-test-server": "^0.2.1",
-    "@nextcloud/eslint-config": "^8.4.2",
+    "@nextcloud/eslint-config": "^9.0.0",
     "@nextcloud/prettier-config": "^1.2.0",
     "@nextcloud/stylelint-config": "^3.1.0",
-    "@nextcloud/vite-config": "^1.5.6",
+    "@nextcloud/vite-config": "^2.0.0",
     "@playwright/test": "^1.52.0",
+    "@vitejs/plugin-vue": "^5.0.0",
+    "@vue/compiler-sfc": "^3.4.0",
     "@vue/tsconfig": "^0.5.1",
+    "eslint": "^8.0.0",
     "eslint-config-prettier": "^10.1.5",
+    "eslint-plugin-vue": "^9.0.0",
     "prettier": "^3.5.3",
-    "vite": "^6.3.5"
+    "sass": "^1.60.0",
+    "vite": "^5.0.0"
   },
   "engines": {
     "node": "^20.0.0",