Fix silent rendering errors in Cloudflare adapter workerd prerenderer

[astrobot-houston]

Changes

• Builds now properly fail when components throw errors during workerd prerendering, instead of silently producing truncated HTML with exit code 0
• Dev mode now displays Astro's error overlay when rendering errors occur, matching the behavior of regular Astro dev servers
• Creates separate non-streaming app instance for prerender requests so errors propagate synchronously as 500 responses instead of being deferred
• Adds missing !response.ok check in prerenderer's render() method to detect and throw on error responses
• Wraps response body streams in dev mode to catch mid-stream errors and inject error overlay scripts

Testing

• Added prerenderer-render-errors.test.ts that verifies builds fail with clear error messages when components have missing imports
• Test fixture includes intentionally broken component to trigger ReferenceError during rendering
• Verified fix works for both build and dev modes with the issue reporter's test case

Docs

• No docs update needed, this fixes broken behavior to match expected Astro error handling.

Closes #16809

[changeset-bot]

🦋 Changeset detected

Latest commit: 76eec04

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

This PR includes changesets to release 38 packages

Name	Type
@astrojs/cloudflare	Patch
@test/astro-cloudflare-node-prerender-mdx	Patch
@test/astro-cloudflare	Patch
@test/astro-cloudflare-allowed-hosts	Patch
@test/astro-cloudflare-astro-dev-platform	Patch
@test/astro-cloudflare-astro-env	Patch
@test/astro-cloudflare-binding-image-service	Patch
@test/astro-cloudflare-cache-provider-wait-until	Patch
@test/astro-cloudflare-client-address	Patch
@test/astro-cloudflare-compile-image-service	Patch
@test/astro-cloudflare-custom-entryfile	Patch
@test/astro-cloudflare-dev-image-endpoint	Patch
@test/astro-cloudflare-external-image-service	Patch
@test/astro-cloudflare-external-redirects	Patch
@test/astro-cloudflare-internal-redirects	Patch
@test/astro-cloudflare-no-output	Patch
@test/astro-cloudflare-prerender-node-env	Patch
@test/astro-cloudflare-prerender-queue-consumers	Patch
@test/astro-cloudflare-prerender-styles	Patch
@test/astro-cloudflare-prerenderer-errors	Patch
@test/astro-cloudflare-prerenderer-render-errors	Patch
@test/routing-priority-cloudflare	Patch
@test/cf-server-entry	Patch
@test/astro-cloudflare-server-island-prerender-framework	Patch
@test/astro-cloudflare-sessions	Patch
@test/astro-cloudflare-sql-import	Patch
@test/cf-ssr-deps	Patch
@test/astro-cloudflare-static	Patch
@test/astro-cloudflare-svelte-rune-deps	Patch
@test/astro-cloudflare-top-level-return	Patch
@test/cf-user-optimize-deps	Patch
@test/astro-cloudflare-vite-plugin	Patch
@test/astro-cloudflare-with-base	Patch
@test/astro-cloudflare-with-react	Patch
@test/astro-cloudflare-with-solid-js	Patch
@test/astro-cloudflare-with-svelte	Patch
@test/astro-cloudflare-with-vue	Patch
@test/astro-cloudflare-wrangler-preview-platform	Patch

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