feat(types): type hints for hmr events

[94726]

Description

This adds type hints for hmr event names (hot.on, hot.off, hot.send).
These are pretty much only for QOL as types aren't enforced, to still allow untyped custom events by vite plugins.

[sapphi-red]

It sounds a nice addition to me 👍

[sapphi-red]

/ecosystem-ci run

[pkg-pr-new]

Open in Stackblitz

npm i https://pkg.pr.new/vite@19579

commit: c364e37

[vite-ecosystem-ci]

📝 Ran ecosystem CI on c364e37: Open

suite	result	latest scheduled
sveltekit	❌ failure	✅ success
vite-plugin-svelte	✅ success	❌ failure

✅ analogjs, astro, histoire, ladle, laravel, marko, nuxt, previewjs, quasar, qwik, rakkas, react-router, storybook, unocss, vike, vite-environment-examples, vite-plugin-pwa, vite-plugin-react, vite-plugin-react-swc, vite-plugin-vue, vite-plugin-cloudflare, vite-setup-catalogue, vitepress, vitest, vuepress, waku

[sapphi-red]

The SvelteKit error is caused by this line.
https://github.com/sveltejs/kit/blob/75efd882e09ba7a1bd7f617de99b4b1a802c27c9/packages/kit/test/apps/basics/src/routes/load/fetch-asset/%2Bpage.js#L1-L3
#19566 added the module definition and thus this @ts-expect-error is no longer used. So it should be fine.