feat: use a single transport for fetchModule and HMR support

[sapphi-red]

Description

so that env providers not need to implement both fetchModule transport and HMR transport.

I think this PR still needs to polish the naming and probably better to introduce a interface that wraps HotChannel so that env providers does not need to care about internal conversion that is done for send and invoke (done).

The upper part is how it was before and the lower part is how it is after.

[stackblitz]

Run & review this pull request in StackBlitz Codeflow.

[sapphi-red]

I polished the interface so that it's more easier to implement for the env providers. I think we need a better name and check if this is not breaking a code that was working in 5.x.

[sheremet-va]

@bluwy pointed out the inconsistency in the naming of RunnerTransport in #16358 (comment)

Should we also standardise it here?

[sapphi-red]

/ecosystem-ci run

[vite-ecosystem-ci]

📝 Ran ecosystem CI on 38b50bf: Open

suite	result	latest scheduled
astro	❌ failure	❌ failure
remix	❌ failure	❌ failure
sveltekit	❌ failure	❌ failure
vike	❌ failure	❌ failure
vite-environment-examples	❌ failure	✅ success
vitest	❌ failure	❌ failure

✅ analogjs, histoire, ladle, laravel, marko, nuxt, previewjs, quasar, qwik, rakkas, redwoodjs, storybook, unocss, vite-plugin-pwa, vite-plugin-react, vite-plugin-react-swc, vite-plugin-svelte, vite-plugin-vue, vite-setup-catalogue, vitepress, vuepress

[sapphi-red]

I've updated the docs (maybe it should contain a bit more explaination about the HotChannel). It's now ready.

This is how the diff looks like after this PR: sapphi-red/daienjo-architecture@804cb53

---

I'm not going to implement it in this PR, but it would be nice if we can use the default WebSocketServer for multiple envs. For example, using it from the service worker env as well.

[sheremet-va]

Should we throw an error instead? 🤔 If hmr is provided, then I would assume the transport supports it

[sapphi-red]

I changed the way in f08a2df and fddfd64, along with the following comments.

[sapphi-red]

Exported env.getInvokeHandler (7536dfb) and tweaked some types (05413c6) to reduce required knowledge on the runtime provider side (sapphi-red/daienjo-architecture@6b91f25).