fix: ensure policies are respected

[MujkicA]

Ensures that set gas limit and max fee policies take precedence over estimated values.

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[MujkicA]

It seems we made gas limit part of the policies even though that doesn't match the specs.

It is convenient to have these knobs all in one place but it might cause confusion if we differ from the underlying system>
It's also a problem when trying to inspect the policies of an executed transaction since we can't easily convert from cores Policy type to our TxPolicies.

We should address this in a future update.

The base branch was changed.