Port Nuxt & Nitro E2E test apps to span streaming

Port these E2E test applications to span streaming (8 apps).

## Apps

* nitro-3
* nuxt-3
* nuxt-3-dynamic-import
* nuxt-3-min
* nuxt-3-top-level-import
* nuxt-4
* nuxt-4-cloudflare
* nuxt-5

## What to do

For each app:

1. Remove the `traceLifecycle: 'static'` pin added in #22590 from every `Sentry.init` (client, server, edge).
2. Rewrite the specs from transaction envelopes to span v2:
* `waitForTransaction` becomes `waitForStreamedSpan` / `waitForStreamedSpans`
* `event.transaction` becomes `span.name`
* `contexts.trace.op` becomes `getSpanOp(span)` plus `span.is_segment`
* `contexts.trace.data['x']` becomes `span.attributes['x']`, which has the shape `{ value, type }`
* `transaction_info.source` becomes the `sentry.segment.name.source` attribute
3. Streamed child spans arrive across several envelopes, so use `collectStreamedSpans` wherever a test asserts on children of a segment span.

Watch the low-cardinality names for `http.server` and for Nuxt db spans.

Reference apps: `nextjs-16-streaming` and `react-router-7-spa-streaming`. Worked example: getsentry/sentry-javascript#23797.

## Keep static trace lifecycle coverage

Before porting this group, duplicate `nuxt-4` as-is into `nuxt-4-static` and leave that copy on the current transaction-based specs. That keeps the static trace lifecycle covered once the rest of the group moves to streaming.

The copy is verbatim; only the app name changes:

* `package.json` -> `name`
* `start-event-proxy.mjs` -> `proxyServerName`
* every `waitForTransaction` / `waitForError` / `waitForSession` call in `tests/`

Keep `traceLifecycle: 'static'` in the copy's `Sentry.init` calls. The e2e matrix discovers apps by directory, so no CI config change is needed.

The representative is a suggestion: swap it if another app in the list exercises more of this SDK's instrumentation.