feat(optimizer): check optimizeDeps.extensions for scannable files

[DylanPiercey]

Description

Updates the isScannable logic to include extensions registered via optimizeDeps.extensions.
This allows plugins (such as @marko/vite) to contribute to the optimized dependency scanning if they supply an esbuild plugin.

Additional context

Currently due to the way @marko/vite is setup it relied exclusively on optimizeDeps.include and not the dependency scanning so adding this change does break existing Marko apps.

However @marko/vite is being updated to use optimizeDeps.entries instead since the include method we were using needlessly bundles more than necessary.

The actual processing of Marko files is done by an esbuild hook added by @marko/vite so no further change is needed here other than allowing .marko files to pass through the isScannable checks.

This issue was addressed in a different way in #14536 and so if this solution is deemed better we can close that PR.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[DylanPiercey]

Actually hold on a second my logic isn't correct in the isScannable implementation.

[DylanPiercey]

@bluwy it should be good now. Let me know if you have any feedback on this implementation!

[DylanPiercey]

@bluwy I went ahead and reverted to my original implementation (with path.extname).

[bluwy]

Awesome. Thanks! Will wait for one more set of eyes for this since it's expanding an existing feature.

[DylanPiercey]

@bluwy is there a timeline for the Vite 5 release? If it's expected to be a while it would be nice for us if this could be backported. 🙏

[bluwy]

The Vite 5 stable release is planned mid October, though with the progress so far it could be a little late, but shouldn't extend till next month.

I don't think this fix could be backported though, it's leaning towards a bigger change that could affect downstream (actually let me run this through ecosystem-ci). If we would to backport something, I think it would be #14536 instead.

[bluwy]

/ecosystem-ci run

[vite-ecosystem-ci]

📝 Ran ecosystem CI: Open

suite	result
analogjs	✅ success
astro	✅ success
histoire	✅ success
ladle	✅ success
laravel	✅ success
marko	✅ success
nuxt	✅ success
nx	✅ success
previewjs	✅ success
qwik	❌ failure
rakkas	✅ success
sveltekit	✅ success
unocss	✅ success
vike	✅ success
vite-plugin-pwa	✅ success
vite-plugin-react	✅ success
vite-plugin-react-pages	✅ success
vite-plugin-react-swc	✅ success
vite-plugin-svelte	✅ success
vite-plugin-vue	✅ success
vite-setup-catalogue	✅ success
vitepress	✅ success
vitest	❌ failure

[patak-dev]

This makes sense to me, and it kind of feels more like a fix than a new feature. I think we can merge it.