feat: make StartCmd more customizable (backport #16209)

[mergify]

This is an automatic backport of pull request #16209 done by Mergify.
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	both modified:   CHANGELOG.md
	both modified:   server/start.go

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[julienrbrt]

blocked on #16207

[tac0turtle]

i dont think we should backport this

[julienrbrt]

i dont think we should backport this

This one is somewhat not breaking, but because one option has an argument that is available only in #16207 it is blocked.
It's a good improvement that we could indeed keep for Eden however 👍🏾