Epic: pending/proven chains with reorg support

[just-mitch]

We want to decouple the pending/proven chain from the view of the rollup contract.

### Tasks
- [ ] #7592
- [ ] #7594
- [ ] https://github.com/AztecProtocol/aztec-packages/issues/7615
- [ ] https://github.com/AztecProtocol/aztec-packages/issues/7616
- [ ] feat: Better estimation of proposer for future L1 time
- [ ] https://github.com/AztecProtocol/aztec-packages/issues/7656
- [ ] https://github.com/AztecProtocol/aztec-packages/issues/7587
- [ ] https://github.com/AztecProtocol/aztec-packages/issues/7579
- [ ] https://github.com/AztecProtocol/aztec-packages/issues/8034