Ensure that `await headers()` is scoped to a render pass rather than only to the surrounding HTTP request. A single request can render the same React tree in multiple passes with different `connection()` semantics, including the prospective and final prerenders of a runtime prefetch and a navigation's dynamic render alongside the runtime prerender spawned to refresh the prefetch cache.

Each pass must resolve `headers()` to its own readonly object identity while exposing the same underlying request-header data. Within a pass, the resolved value should consistently identify that pass. This must prevent userland memoization keyed by the resolved headers object from carrying pending or rejected work into another pass: runtime-prefetch work must not prevent a subsequent navigation's dynamic content from completing, and aborted prerender work must not leak into request error handling. Preserve existing header values and readonly API guarantees.