fix(astro): prevent crash when deleting an injected route's entrypoint in dev

[lx3133584]

Changes

• Fix unhandled rejection / server crash in dev mode when an injected route's entrypoint is deleted or renamed (Deleting an injected route's entrypoint in dev crashes the server under @astrojs/cloudflare (unhandled rejection in the routes rebuild) #18325).
• In dev mode, when createRoutesList() reads route component content for prerender options and encounters ENOENT (e.g. when an integration injected route points to a file that was deleted or renamed during dev), catch the error and log a warning instead of throwing, allowing other routes to continue rebuilding and functioning normally.
• In rebuildRoutes() within vite-plugin-routes, wrap the route rebuild in a try/catch block to ensure watcher event listeners do not emit unhandled promise rejections.
• In build mode, missing route entrypoints continue to throw an error as expected.
• Added a patch changeset for astro.

Fixes #18325

Testing

• Added unit tests in packages/astro/test/units/routing/manifest.test.ts:
  • in dev mode, does not throw when an injected route entrypoint does not exist
  • in build mode, throws when an injected route entrypoint does not exist
• Ran all 305 routing unit tests (./node_modules/.bin/astro-scripts test "test/units/routing/*.test.ts" --strip-types) with 100% pass rate.
• Verified monorepo typecheck passes (pnpm run typecheck).

Docs

Bug fix only; does not change public documentation or API surface.

🤖 Generated with Claude Code

[changeset-bot]

🦋 Changeset detected

Latest commit: 4b9993d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
astro	Patch

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[codspeed]

Merging this PR will not alter performance

⚠️ 3 benchmarks spent significant time in system calls

System calls cannot be consistently instrumented, so they are not included in the measure, which understates the real cost. Please switch to the Walltime instrument to accurately measure system calls.

Measurement and system calls

• Build: full server site
• Build: hybrid site (static + server)
• Build: full static site

ℹ️ 13 benchmarks have no flame graph

The flamegraph could not be generated because too much time was spent in runtime internals, making the visualization not useful for performance analysis.

• Build: full server site
• head-propagation-2000 [streaming]
• large-array [streaming]
• many-components [streaming]
• head-propagation-2000 (propagator collection, 2x scale)
• many-slots (eager slot prerendering)
• many-head-elements (head dedup)
• head-propagation-1000 (propagator collection)
• large-array (BufferedRenderer per child)
• many-components (markHTMLString, isHTMLString, validateProps)
• …and 3 more

✅ 21 untouched benchmarks

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_{Comparing lx3133584:fix/dev-injected-route-unlink-crash (4b9993d) with main (a85847e)¹}

Footnotes

1. No successful run was found on main (9050e38) during the generation of this report, so a85847e was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩