How to support define options.

[underfin]

Because the vite use esbuild define option at optimizer, the rollup has [@rollup/plugin-replace](https://github.com/rollup/plugins/tree/master/packages/replace#rollupplugin-replace) to do it, it using string match to replace, it is performance friendly but other ecosystem using last to do it, eg swc/webpack.

I think we can use @rollup/plugin-replace to do it at milestone 1. It means we need to support some plugin API for the plugin, it is easy to implement.
But we need re-think it how to support it at rolldown for better performance and correct replace result.

[kazupon]

I am interested in this issue and making the plugin work.

we consider performance, I think the plugin should be implemented on the Rust side.
However, we would ideally like to keep it compatible with the existing rollup plugin.
Do you have in your team about a plugin plan, how to implemetation idea?