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/operator/server/utils/platform-api.ts

@@ -26,7 +26,11 @@ function originatingIp(event: H3Event): string | undefined {
 export async function platformApi<T = unknown>(
   event: H3Event,
   path: string,
-  init: { method?: string; body?: unknown; query?: Record<string, string | number | undefined> } = {},
+  init: {
+    method?: string
+    body?: BodyInit | Record<string, unknown> | null
+    query?: Record<string, string | number | undefined>
+  } = {},
 ): Promise<T> {
   const session = await getUserSession(event).catch(() => null)
   const accessToken = (session as { accessToken?: string } | null)?.accessToken