Support ESM plugins and async plugin hooks

[vjpr]

Issue description or question

Error [ERR_REQUIRE_ESM]: require() of ES Module ./xxx/quokka-plugin-live/index.js from ./index.js not supported.
Instead change the require of ./xxx/quokka-plugin-live/index.js in ./index.js to a dynamic import() which is available in all CommonJS modules.
    at Array.forEach (<anonymous>)
    at new Promise (<anonymous>)

I need to run some async code in a hook. This would allow to dynamic import ESM modules.

Ideally I would prefer to write an ESM module for the entire plugin.