fix: prepare local Container sidecars without configured images

[th0m]

Fixes #CC-8733

Wrangler dev and Vite dev/preview skipped preparation when Containers had no configured application images. On a clean Docker cache, selecting an image through start() failed because the required egress sidecar was missing.

Prepare images whenever local Containers are enabled and configured, including when the application image list is empty. Preserve reload deduplication, retry behavior, per-worker registry authentication, and runtime image selection.

Validation:

• 61 focused tests passed, including new sidecar-only preparation, disabled/absent Containers, reload/retry, and multiworker coverage.
• Relevant builds, type checks, lint, and formatting passed locally.
• Added Docker-backed CI tests for Wrangler dev and Vite dev/preview with the application image preloaded and the sidecar absent. Execution is pending CI.

---

• 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: local dev bug fix

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

---

[changeset-bot]

🦋 Changeset detected

Latest commit: c0620ff

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-plugin	Patch

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[workers-devprod]

Codeowners approval required for this PR:

• ✅ @cloudflare/cloudchamber
• ✅ @cloudflare/wrangler

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commit: c0620ff

[ask-bonk]

LGTM

github run

[cjol]

Devin's remaining comment seems legit,but not a blocker

[workers-devprod]

Codeowners reviews satisfied

[th0m]

Devin's remaining comment seems legit,but not a blocker

Thanks for the quick review @cjol I've reworked the clean up logic and looks like Devin is happy now.