Should `getFirst` have an alias `setLimit`
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### Summary

I'm not sure I get all the steps correctly, but if so:
As discussed in [discord thread](https://discord.com/channels/489127045289476126/1346789719954161756), setFirst is not very expected on pg class steps. In the channel Benjie proposed to "I should probably add a `setLimit` alias for `setFirst`", which, in my opinion may add a confusion. What I would rather expect, to only have  `setLimit`, as we are in the context of PgClass step. `setFirst` makes more sense when we are in the context of `connection` step.

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