Bundle the `'use cache'` deadlock probe worker (#93538)
Follow-up to #93500.
The probe worker (`use-cache-probe-worker.ts`) ships as plain `tsc`
output and `require()`s
`react-server-dom-webpack/server` directly. The merged PR added a
require-hook entry covering only that one specifier, which is not
enough. The vendored RSC binding itself does plain `require('react')`
and `require('react-dom')`, and with `--conditions=react-server` set on
the worker those fall through to the user's installed React. For any
Next.js app on React 18 that means React 18's `react.shared-subset`, a
stub that throws `"not yet supported outside of experimental channels"`.
The probe crashes the moment it spawns. Default canary tests didn't
catch this — their installed React 19 supports the `react-server`
condition — but running the suite with
`NEXT_TEST_REACT_VERSION="18.3.1"` surfaced it.
Adding more hook entries to cover `react`, `react-dom`, etc. would mean
manually mirroring the `${bundler} × ${reactChannel}` matrix that
`makeAppAliases` and the `react-server` layer rule in
`next-runtime.webpack-config.js` already encode for `react`,
`react-dom`, `react/jsx-*`, and
`react-server-dom-{webpack,turbopack}/*`.
The worker is now bundled through that pipeline as a new `'app-worker'`
bundleType, which inherits the alias matrix and is included in the
`react-server.node` layer rule. Four dev-only tasks (`{turbo,webpack} ×
{experimental,stable}`) produce the four artifacts. In
`use-cache-probe-pool.ts` when the pool is created we resolve the
matching bundle via `process.env.TURBOPACK` and
`needsExperimentalReact(nextConfig)`.
The worker source uses a plain static import of
`react-server-dom-webpack/server`, as we do everywhere else. The
require-hook entry is deleted, and `--conditions=react-server` is no
longer added to `NODE_OPTIONS` since all React specifiers resolve to
absolute paths at build time.
