fix(x/consensus): harden consensus params proposal

[tac0turtle]

Description

replaces: #20314

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[julienrbrt]

Can we get a changelog?
I the rationale: it is consensus breaking but as the chain would have halted if that wrongly gov proposal were submitted, we consider it safe to backport?

[tac0turtle]

Can we get a changelog? I the rationale: it is consensus breaking but as the chain would have halted if that wrongly gov proposal were submitted, we consider it safe to backport?

I need to spend some time seeing if it's breaking. I think the current design is fine but need to check as well

[julienrbrt]

I think compared to other consensus breaking where the chain would have panicked immediately, this will require a rollback of the latest block for those crashing, instead of simply switching binaries.

However you could predict this issue is going to reach a chain miles ahead, as it is via a proposal.

[testinginprod]

I think it's ok to backport to 0.50 even if it is consensus breaking.

[julienrbrt]

Seems like some tests are failing: https://github.com/cosmos/cosmos-sdk/actions/runs/9079625767/job/24949587121?pr=20381