SSR webworker output options are set too early in Vite 6

[bluwy]

Describe the bug

Particularly this code:

vite/packages/vite/src/node/build.ts

Lines 456 to 467 in ae68958

	if (isSsrTargetWebworkerEnvironment) {
	resolved.rollupOptions ??= {}
	resolved.rollupOptions.output ??= {}
	const output = resolved.rollupOptions.output
	for (const out of arraify(output)) {
	out.entryFileNames ??= `[name].js`
	out.chunkFileNames ??= `[name]-[hash].js`
	const input = resolved.rollupOptions.input
	out.inlineDynamicImports ??=
	!input || typeof input === 'string' || Object.keys(input).length === 1
	}
	}

We're computing the output options when resolving the config, however plugins could change the output options, or even the input options (that affects how inlineDynamicImports is computed) during the config() or options() hooks.

In Vite 5, we were computing only at the last step when generating the outputs:

vite/packages/vite/src/node/build.ts

Lines 672 to 682 in 5da6895

	chunkFileNames: libOptions
	? `[name]-[hash].${jsExt}`
	: path.posix.join(options.assetsDir, `[name]-[hash].${jsExt}`),
	assetFileNames: libOptions
	? `[name].[ext]`
	: path.posix.join(options.assetsDir, `[name]-[hash].[ext]`),
	inlineDynamicImports:
	output.format === 'umd' ||
	output.format === 'iife' ||
	(ssrWorkerBuild &&
	(typeof input === 'string' || Object.keys(input).length === 1)),

---

This was affecting Astro's Cloudflare integration where it uses SSR webworker and manualChunks, but since inlineDynamicImports is computed early and set as true (should be false as Astro later adds inputs in config() hook), it causes Rollup to throw with:

Invalid value for option "output.manualChunks" - this option is not supported for "output.inlineDynamicImports".

Reproduction

Sorry none for now

Steps to reproduce

No response

System Info

n/a

Used Package Manager

npm

Logs

No response

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