[FEATURE] Sequencer catchup on restart from base

[julienrbrt]

With the introduction of force included transactions, users are able to continue to use the chain when the sequencer becomes unavailable or malicious.

Currently, only the malicious case is implemented. This case is irrecoverable and nodes should be using base sequencing in order to keep using the chain.
The case where the sequencer becomes unavailable for more than one DA epoch is however not yet implemented.
This needs to be implemented as disaster recovery, in case both the sequencer and their subordinates (using high availability) are failing for a long period.

When the sequencer comes back online, it has to assume other nodes switched to base sequencing for the missing DA epoch. The sequencer must catch-up missed DA epoch and produce the same blocks.
Once it has reached the head, the sequencer can start producing blocks again.

[julienrbrt]

I do believe on the sync part, switching from base sequencing to sync node should remain a manual operation.