Use incremental build feature of esbuild

[schickling]

Thanks again for this great tool @rsms 🙏

To speed up estrella further when continuously rebuilding a project, it's now possible to use the new incremental build feature.

Note: I've done some quick scan of the code base if this is already the case but couldn't find any indication for this. If you're already using esbuild's incremental build feature, please just close this issue.

[rsms]

Great idea! Happy to accept a PR for this, by the way.

[myobie]

{ incremental: !!cliopts.watch } appears to me to be passed through to esbuild. Is there more to do than just include it in the build arguments?

[rsms]

Added in 7a2bd8f (forgot to mention the GitHub issue) and will be included with the next release.