[RNM] Extract Rollup node manager components as separate tasks

[greged93]

The Rollup node manager currently handles the orchestration of various components, by polling them in its Future implementation. This simplifies the understanding of how futures are polled, but incurs a performance cost. Some components could be ran as separate tasks in order to increase performance, as they wouldn't have to wait on the Rollup node manager to poll them in order to progress.

Evaluate the performance to lost of scheduling for the various components and decide if we want to move some of these components as separate tasks, similar to the L1Watcher. Proper benchmarking for the performance of the node should be set in place in order to correctly evaluate performance improvements.