Interop: persist index of cross-safe and local-safe increments per L1 block

[protolambda]

cross-safe accuracy depends on reasoning what L2 block is derived from what L1 block.
This information is not registered onchain, as it can only be reasoned about after posting the batch that confirms the data.
Consistency and completeness of this offchain data is challenging.

To serve the data needed to limit cross-validation to a particular L1 view (see #12075 ) we need to maintain a mapping of what L2 block was derived from what L1 block.
There is a design-doc covering this here.

We do not need the reorg support with Devnet 1, but do want to maintain a minimal index of the required safety information to provide accurate cross-safe and finalized L2 block information to the user.