In-memory tree states (#5533)

* Consensus changes

* EF tests

* lcli

* common and watch

* account manager

* cargo

* fork choice

* promise cache

* beacon chain

* interop genesis

* http api

* lighthouse

* op pool

* beacon chain misc

* parallel state cache

* store

* fix issues in store

* IT COMPILES

* Remove some unnecessary module qualification

* Revert Arced pubkey optimization (#5536)

* Merge remote-tracking branch 'origin/unstable' into tree-states-memory

* Fix caching, rebasing and some tests

* Remove unused deps

* Merge remote-tracking branch 'origin/unstable' into tree-states-memory

* Small cleanups

* Revert shuffling cache/promise cache changes

* Fix state advance bugs

* Fix shuffling tests

* Remove some resolved FIXMEs

* Remove StateProcessingStrategy

* Optimise withdrawals calculation

* Don't reorg if state cache is missed

* Remove inconsistent state func

* Fix beta compiler

* Rebase early, rebase often

* Fix state caching behaviour

* Update to milhouse release

* Fix on-disk consensus context format

* Merge remote-tracking branch 'origin/unstable' into tree-states-memory

* Squashed commit of the following:

commit 3a16649023
Author: Michael Sproul <michael@sigmaprime.io>
Date:   Thu Apr 18 14:26:09 2024 +1000

    Fix on-disk consensus context format

* Keep indexed attestations, thanks Sean

* Merge branch 'on-disk-consensus-context' into tree-states-memory

* Merge branch 'unstable' into tree-states-memory

* Address half of Sean's review

* More simplifications from Sean's review

* Cache state after get_advanced_hot_state

consensus/state_processing/src/per_epoch_processing/altair/participation_flag_updates.rs

@@ -2,17 +2,14 @@ use crate::EpochProcessingError;
 use types::beacon_state::BeaconState;
 use types::eth_spec::EthSpec;
 use types::participation_flags::ParticipationFlags;
-use types::VariableList;
+use types::List;
 
 pub fn process_participation_flag_updates<E: EthSpec>(
     state: &mut BeaconState<E>,
 ) -> Result<(), EpochProcessingError> {
     *state.previous_epoch_participation_mut()? =
         std::mem::take(state.current_epoch_participation_mut()?);
-    *state.current_epoch_participation_mut()? = VariableList::new(vec![
-        ParticipationFlags::default(
-        );
-        state.validators().len()
-    ])?;
+    *state.current_epoch_participation_mut()? =
+        List::repeat(ParticipationFlags::default(), state.validators().len())?;
     Ok(())
 }