Describe the feature

tsup is ~officially in maintenance mode in favor of tsdown.
tsdown is a lot faster, I migrated my packages over a few months ago, I've got a branch lying around for sheriff (lishaduck:faster-simpler-bundles/ 15fc727), it was a lot faster. It was blocked on noexternal, but it's since been implemented (rolldown/tsdown#57).

Motivation

It was a lot faster when I last tested it.

Projects

eslint-config-sheriff, @sherifforg/cli, @sherifforg/create-config

Code of Conduct

• I agree to follow this project's Code of Conduct
• I have read the Contributing Guidelines on Issues.

I will submit a PR

• I'd be willing to submit a PR for this issue.