Minimal repro for a build crash with @astrojs/cloudflare when experimental.advancedRouting uses a custom fetchFile.

pnpm install
pnpm build

(0 , __vite_ssr_import_0__.createGetEnv) is not a function
  at runInRunnerObject (workers/runner-worker/index.js:107:3)

• src/worker.ts is the fetchFile. It imports cf from @astrojs/cloudflare/fetch.
• Set experimental.advancedRouting to true and the build passes, because virtual:astro:fetchable falls back to DefaultFetchHandler and never imports @astrojs/cloudflare/fetch.
• It's a circular import: fetch.js runs setGetEnv(createGetEnv(globalEnv)) and createApp() at module top level. createApp comes from astro/app/entrypoint, which imports virtual:astro:fetchable, which re-exports worker.ts, which imports @astrojs/cloudflare/fetch again.
• Importing cf lazily inside the handler (const { cf } = await import('@astrojs/cloudflare/fetch')) breaks the static back-edge and the build passes.