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Sanskrit also lacked a single affirmative particle, instead using various words/phrases meaning "true" or "it is so" (sat, satya, astu)

Also similar to Latin, most of it's daughter languages standardized on a single affirmative particle "haan".

Astu (अस्तु) is imperative, asti, (अस्ति) is what would be used.

Either works depending on the context. "astu" is more like "let it be so". Still, there is no single generic affirmative particle.

I believe the direct cognate of this in Latin is "esto".