fix(build): handle preload treeshaking for braces

[bluwy]

Description

fix #17478

Handle the cases shown in the issue above. The third part of the regex was to lax to support import(...).then(function ({ ... }) so I tighten it up so it's not too greedy.

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While fixing this, I started to notice that regexes would fall apart as long as someone sets fallback values, like:

const { foo = "fallback" } = await import(...)

await import(...).then(({ foo = "fallback" }) => {})

The "fallback" could be anything that tricks the regex to end early. However, I think it's very rare for dynamic imports to have fallback values, so we can see how far regex goes before needing to go with an AST approach. Or maybe until then we can rethink preload transforms.

[stackblitz]

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[bluwy]

/ecosystem-ci run

[patak-dev]

Let's merge the fix. Maybe we should bailout of the optimization if we detect a fallback?

[bluwy]

Now that you mention it, it's actually not that hard to bail out, by checking if the matched part as a = 🤔

[vite-ecosystem-ci]

📝 Ran ecosystem CI on dd93fd0: Open

suite	result	latest scheduled
nuxt	❌ failure	❌ failure
sveltekit	❌ failure	✅ success
vite-plugin-react-pages	❌ failure	❌ failure
vitest	❌ failure	❌ failure

✅ analogjs, astro, histoire, ladle, laravel, marko, previewjs, quasar, qwik, rakkas, remix, unocss, vike, vite-plugin-pwa, vite-plugin-react, vite-plugin-react-swc, vite-plugin-svelte, vite-plugin-vue, vite-setup-catalogue, vitepress