chore(portal,operator): upgrade to Nuxt 4

Upgrade both Nuxt apps to Nuxt 4.4.6 (vue-tsc 3, TypeScript 5.6, undici 7) and add a root tsconfig.json to each app. Fix the strict-null / noUncheckedIndexedAccess errors surfaced by Nuxt 4's stricter generated tsconfig and vue-tsc 3. Drop the nuxt-oidc-auth pnpm patch (Nuxt 4 fixes the prepare:types crash natively).

apps/portal/package.json

@@ -2,7 +2,7 @@
   "name": "@dezky/portal",
   "version": "0.0.1",
   "private": true,
-  "description": "Dezky customer-facing portal — Nuxt 3",
+  "description": "Dezky customer-facing portal — Nuxt 4",
   "scripts": {
     "dev": "nuxt dev --host 0.0.0.0 --port 3000 --dotenv ../../.env",
     "build": "nuxt build",
@@ -11,14 +11,16 @@
     "lint": "eslint ."
   },
   "dependencies": {
-    "nuxt": "^3.13.0",
+    "nuxt": "^4.4.6",
     "nuxt-oidc-auth": "1.0.0-beta.11",
+    "undici": "^7.2.1",
     "vue": "^3.5.0",
     "vue-router": "^4.4.0"
   },
   "devDependencies": {
     "@types/node": "^20.0.0",
-    "typescript": "^5.5.0"
+    "typescript": "^5.6.0",
+    "vue-tsc": "^3.2.6"
   },
   "packageManager": "pnpm@9.12.0"
 }