feat: integrate base fee computation into rollup contract

[LHerskind]

Integrate the fee model from #9804 into the rollup contract such that the value is used in computations. If happening before #9868, keep that value zero, so we still have a variable base-fee, just without the congestion multiplier.

For the oracle input for #9718 we should for now just keep them 0, but get back to it when we have improved knowledge.