[wrangler] Improve asset upload performance with single-file uploads

[jbwcloudflare]

Fixes #WC-4107

Begin onboarding wrangler to use the improved API endpoint for uploading Workers Assets.
This is being staged as a gradual rollout:

• By default, users will continue to use the existing wrangler codepath and API endpoint.
• Users that are opted-in to the new feature (controlled on the server side) will use the new endpoint.

This allows us to gradually roll out and validate the new feature without a hard cutover during a new wrangler release, or the need for emergency wrangler patch releases if something goes wrong.

• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: not a new feature just an implementation detail change

A picture of a cute animal (not mandatory, but encouraged)

[changeset-bot]

🦋 Changeset detected

Latest commit: 5d74650

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

This PR includes changesets to release 3 packages

Name	Type
wrangler	Patch
@cloudflare/vite-plugin	Patch
@cloudflare/vitest-pool-workers	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[pkg-pr-new]

create-cloudflare

npm i https://pkg.pr.new/create-cloudflare@14305

@cloudflare/deploy-helpers

npm i https://pkg.pr.new/@cloudflare/deploy-helpers@14305

@cloudflare/kv-asset-handler

npm i https://pkg.pr.new/@cloudflare/kv-asset-handler@14305

miniflare

npm i https://pkg.pr.new/miniflare@14305

@cloudflare/pages-shared

npm i https://pkg.pr.new/@cloudflare/pages-shared@14305

@cloudflare/unenv-preset

npm i https://pkg.pr.new/@cloudflare/unenv-preset@14305

@cloudflare/vite-plugin

npm i https://pkg.pr.new/@cloudflare/vite-plugin@14305

@cloudflare/vitest-pool-workers

npm i https://pkg.pr.new/@cloudflare/vitest-pool-workers@14305

@cloudflare/workers-auth

npm i https://pkg.pr.new/@cloudflare/workers-auth@14305

@cloudflare/workers-editor-shared

npm i https://pkg.pr.new/@cloudflare/workers-editor-shared@14305

@cloudflare/workers-utils

npm i https://pkg.pr.new/@cloudflare/workers-utils@14305

wrangler

npm i https://pkg.pr.new/wrangler@14305

commit: 5d74650

[workers-devprod]

Codeowners approval required for this PR:

• @cloudflare/wrangler

Show detailed file reviewers

• .changeset/edge-kv-asset-upload.md: [@cloudflare/wrangler]
• packages/deploy-helpers/src/deploy/helpers/assets.ts: [@cloudflare/wrangler]
• packages/deploy-helpers/src/deploy/helpers/jwt.ts: [@cloudflare/wrangler]
• packages/wrangler/src/tests/deploy/assets.test.ts: [@cloudflare/wrangler]
• packages/wrangler/src/tests/deploy/helpers.ts: [@cloudflare/wrangler]
• packages/wrangler/src/pages/upload.ts: [@cloudflare/wrangler]

[devin-ai-integration]

Devin Review found 1 new potential issue.

[devin-ai-integration]

🟡 getEdgeKvUploadConcurrency can return 0 for fractional JWT values between 0 and 1, breaking PQueue

When edge_kv_upload_concurrency in the JWT is a fractional value in the range (0, 1) — e.g. 0.5 — the check value > 0 passes but Math.floor(value) produces 0. PQueue requires concurrency ≥ 1; setting it to 0 will cause the queue to either throw or hang indefinitely, preventing any uploads from completing. While the value is server-controlled (making this unlikely in practice), a simple guard like Math.max(1, Math.floor(value)) or checking value >= 1 would make this robust.

Suggested change

	return value > 0 ? Math.floor(value) : EDGE_KV_UPLOAD_CONCURRENCY;
	return value >= 1 ? Math.floor(value) : EDGE_KV_UPLOAD_CONCURRENCY;

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