refactor: remove micro-util dependencies

[beeequeue]

This PR replaces lodash.map and longest with Array.map() and a small utility function.

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I saw you talking about various issues due to the package being old (#225, #227). I would be up for helping out if you want
I've seen various things that could be done in this and its related packages, feel free to let me know what you think about these ideas (maybe even in its own issue? 😋):

• Replace various micro-utilities with native JS or simple functions (like this PR!)
• Replace chalk with picocolors as it's the one generally used by modern packages like vite
• Upgrade minimum Node version to 20 (since it would allow...)
• Migrating to ESM
• Using node's native test runner instead of mocha