fix(vite-plugin): retry transient module-transport failures in the runner worker

[exKAZUu]

Fixes #14849.

Each fetchModule invoke in the runner worker's module-runner transport was a single fetch to the dev server with no retry. If that one fetch failed transiently (e.g. Network connection lost from the loopback keep-alive race in #14848), Vite's module runner cached the rejection, and every request importing the affected module failed for the rest of the dev session — one transient hiccup out of thousands of module fetches permanently bricked the session until a file edit or dev-server restart.

This change retries the invoke fetch up to three times before giving up. The invoke is an idempotent request for module code, so retrying is safe, and it converts a rare transient transport error into a non-event.

This complements the root-cause fix for the specific trigger I could reproduce (#14848 / #14850): even with that fixed, any other short-lived hiccup on the loopback path would still poison the session without a retry.

---

• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows: the transient failure needs real socket-pool timing, so it is inherently flaky to assert in CI. Manually verified by instrumenting the runner worker in a real app (details in [vite-plugin] A single transient module-transport failure permanently breaks the dev session #14849): on stock Miniflare, cold starts failed on 1–2 of ~3,000 invokes and the session stayed broken; with this retry applied, the same cold starts complete successfully.
  • Additional testing not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: dev-only internal transport robustness fix; no user-facing API change.

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🦋 Changeset detected

Latest commit: 3f166c1

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

This PR includes changesets to release 1 package

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@cloudflare/vite-plugin	Patch

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[workers-devprod]

Codeowners approval required for this PR:

• ✅ @cloudflare/wrangler

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[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.

[pkg-pr-new]

@cloudflare/autoconfig

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@cloudflare/config

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create-cloudflare

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@cloudflare/pages-shared

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@cloudflare/unenv-preset

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@cloudflare/vite-plugin

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@cloudflare/vitest-pool-workers

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@cloudflare/workers-auth

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commit: 3f166c1

[edmundhung]

Thanks for the fix.

I think it is fine to merge without test as the retry is hard to replicate in test environment and the change is small enough. Our existing tests should also cover the happy path.

[workers-devprod]

Codeowners reviews satisfied

[edmundhung]

Don't worry about CI flakes. I will sort them out.