This adds some comments with some useful code pointers for existing
logic and discussing future OCC work

NA

## Describe your changes and provide context
Add multiversion store data structures file, and implement the
multiversioned item

## Testing performed to validate your change
Added unit tests to verify behavior

## Describe your changes and provide context
This adds the incarnation field to the multiversion item data structure.

## Testing performed to validate your change
updated unit tests

## Describe your changes and provide context
This implements the multiversion with basic functionality, but still
needs additional work to implement the iterator functionality and/or
persisting readsets for validation

## Testing performed to validate your change
Added unit tests for basic multiversion store

## Describe your changes and provide context
- `ConcurrencyWorkers` represents the number of workers to use for
concurrent transactions
- since concurrrency-workers is a baseapp-level setting, implementations
(like sei-chain) shouldn't have to pass it (but can)
- it defaults to 10 if not set (via cli default value)
- it defaults to 10 in app.toml only if that file is being created (and
doesn't exist)
- if explicitly set to zero on command line, it will override with the
default (for safety)
- cli takes precedence over the config file
- no one has to do anything to get it to be 10 (no config changes no
sei-chain changes required (aside from new cosmos version))

## Testing performed to validate your change
- Unit Tests for setting the value
- Manually testing scenarios with sei-chain

## Describe your changes and provide context
This adds in functionality to write the latest multiversion values to
another store (to be used for writing to parent after transaction
execution), and also adds in helpers for writeset management such as
setting, invalidating, and setting estimated writesets.

## Testing performed to validate your change
Unit testing for added functionality

## Describe your changes and provide context
- `sei-cosmos` will receive a list of transactions, so that sei-chain
does not need to hold the logic for OCC
- This will make the logic easier to test, as sei-cosmos will be fairly
self-contained
- Types can be extended within a tx and within request/response

Example interaction:
<img
src="https://github.com/sei-protocol/sei-cosmos/assets/6051744/58c9a263-7bc6-4ede-83ab-5e34794510b1"
width=50% height=50%>

## Testing performed to validate your change
- This is a skeleton for a batch interface

## Describe your changes and provide context
This implements an mvkv store that will manage access from a transaction
execution to the underlying multiversion store and underlying parent
store if the multiversion store doesn't have that key. It will first
serve any reads from its own writeset and readset, but if it does have
to fall through to multiversion store or parent store, it will add those
values to the readset.

## Testing performed to validate your change
Unit tests

…ore (#330)

## Describe your changes and provide context
This adds in validation for transaction state to multiversion store, and
implements readset validation for it as well.

## Testing performed to validate your change
Unit Test

## Describe your changes and provide context
- Adds a basic scheduler shell (see TODOs)
- Adds a basic task definition with request/response/index
- Listens to abort channel after an execution to determine conflict

## Testing performed to validate your change
- Compiles (holding off until shape is validated)
- Basic Unit Test for ProcessAll

## Describe your changes and provide context
This implements Iterator and ReverseIterator for mvkv for the KVStore
interface. The memiterator will be composed of versionindexedstore and
multiversionstore, and will yield values in a cascading fashion firstly
from the writeset, and then second from the multiversion store.

This still needs optimization to persisted sorted keys instead of
reconstructing sorted keys each time.

## Testing performed to validate your change
Unit test to verify basic functionality

## Describe your changes and provide context
This fixes a dependency that was refactored, and enables commit push CI
for occ-main

## Testing performed to validate your change
CI

## Describe your changes and provide context
This implements a tracked iterator that is used to keep track of keys
that have been iterated, and to also save metadata about the iteration
for LATER validation. The iterator will be replayed and if there are any
new keys / any keys missing within the iteration range, it will fail
validation. the actual values served by the iterator are covered by
readset validation.

Additionally, the early stop behavior allows the iterateset to ONLY be
sensitive to changes to the keys available WITHIN the iteration range.
In the event that we perform iteration, and THEN write a key within the
range of iteration, this will not fail iteration because we take a
snapshot of the mvkv writeset at the moment of iteration, so when we
replay the iterator, we populate that iterator with the writeset at that
time, so we appropriately replicate the iterator behavior.

In the case that we encounter an ESTIMATE, we have to terminate the
iterator validation and mark it as failed because it is impossible to
know whether that ESTIMATE represents a value change or a delete, since
the latter, will affect the keys available for iteration.

This change also implements handlers that iterators receive for updating
readset and iterateset in the `mvkv`

## Testing performed to validate your change
Unit tests for various iteration scenarios

- This was copied from #332 which became unwieldy due to commit history
(merges/rebases)
- Adds scheduler logic for validation
- In this initial version it completes all executions then performs
validations (which feed retries)
- Once we start benchmarking we can make performance improvements to
this
- Retries tasks that fail validation and have no dependencies

- Scheduler Test verifies multi-worker with conflicts

## Describe your changes and provide context
Some tests from sei-chain don't inject a store, and while I'm not sure
if that's a valid scenario I made the scheduler.go tolerant to the
situation to avoid introducing this assumption to the system.

## Testing performed to validate your change
New unit test confirming lack of crash

## Describe your changes and provide context
- Allows sei-chain to ask isOCCEnabled() so that it can choose to use
the OCC logic
- Sei-chain can set this to true according to desired logic

## Testing performed to validate your change
- unit test that sets flag and verifies value

## Describe your changes and provide context
This adds in the ability to prefill estimates based on metadata passed
along with deliverTxBatch

## Testing performed to validate your change
Unit Test to verify that multiversion store initialization is now
idempotent, and works properly regardless of whether estimate prefill is
enabled

## Describe your changes and provide context
- `CollectIteratorItems` needs to hold an RLock to avoid a concurrent
access panic

## Testing performed to validate your change
- Reproduced through a sei-chain-side test (concurrent instantiates)

## Describe your changes and provide context
This adds the accesscontrol module behavior to add the tx writeset
generation

## Testing performed to validate your change
Unit tests + integration with sei-chain and loadtest cluster testing

## Describe your changes and provide context
- Adds trace span for `SchedulerValidate` 
- Adds trace span for `SchedulerExecute`
- Mild refactor (extracted methods) to make it easier to defer span
ending

## Testing performed to validate your change
Example trace (run locally)

![image](https://github.com/sei-protocol/sei-cosmos/assets/6051744/b8a032f1-71b1-4e95-b12e-357455ebcc6d)

Example attributes of SchedulerExecute operation

![image](https://github.com/sei-protocol/sei-cosmos/assets/6051744/68992e84-4000-44c1-8597-9d4c10583a66)

## Describe your changes and provide context
This fixes the validation to remove a panic for a case that can actually
occur if a transaction writes a key that is later read, and that writing
transaction is reverted and then the readset validation reads from
parent store. In this case, the readset would have a conflict based on
the data available in parent store, so we shouldn't panic. This also
adds in the resource types needed for the new DEX_MEM keys

## Testing performed to validate your change
Tested in loadtest cluster

This makes optimizations to the scheduler and validation

---------

Co-authored-by: Steven Landers <[email protected]>

Add optimizations to reduce mutex lock contention and refactor with sync
Maps. This also removes telemetry that was added liberally, and we can
later add in telemetry more mindfully and feature flagged.

loadtest chain testing

## Describe your changes and provide context
- adds pool optimizations (bounds by tasks / workers)
- adds validateAll shortcut (starts at first non-validated entry)
- adds invalidation of future tasks on invalidation

## Testing performed to validate your change
- unit tests are passing with full conflicting txs

## Describe your changes and provide context
Update concurrency workers

## Testing performed to validate your change

## Describe your changes and provide context
- instead of assuming one thing will arrive to the abort channel, drain
it
## Testing performed to validate your change
- new unit test captures situation (tests iterator)

## Describe your changes and provide context
This change serves to improve the way we track the values of the keys we
iterate over when running iterators. Previously, the iterateset would
only track the keys that were iterated, and the behavior of the iterator
was thought to not include keys that didn't have values present, OR that
the readset would be appropriately updated when reading the value from
the iterateset. (I'm not yet 100% sure that updating readset WITHIN the
tracked iterator is fully necessary, since it may be the case that the
readset modifications may have been sufficient to mitigate this issue,
but the change is currently in the PR since this is the version of code
running on the loadtest cluster for stability testing.

However, in cases when an earlier transaction was writing to the range
that would be iterated, it was possible that the stale value was read by
the transaction handler, BUT the value that got into the readset was the
newer one.

I believe this has to do with the readset updating based on directly
querying values from underlying stores, and overwriting the prior
readset value that indicated that the transaction used a stale value.
The fix I have made is that during tx execution, the cache memiterator
now reads directly form MVKV instead of individually reading from
underlying stores. The key difference here is that IF the key is already
in the readset, it will serve that STALE value instead of reading into
the underlying store where the value may have since mutated. As a
result, the behavior we now expect is that one a key is read, ONLY that
value that was read will be utilized for the duration of the
transaction. This way, we won't potentially mutate the readset by
overwriting the key entry with the later value only to have it
incorrectly pass validation.

Additionally, to more rigorously enforce this behavior, updating the
readset now will only update the map IFF the key doesnt already exist in
the readset. This should provide better guarantees around catching any
stale reads that occur over the lifespan of the transacation execution.

## Testing performed to validate your change
Running a lot of iterator heavy workloads on a loadtest cluster to
verify that no nondeterminism remains in the iterator workflow

## Describe your changes and provide context

## Testing performed to validate your change

## Describe your changes and provide context
This adds `occ-enabled` as a config for baseapp to control whether to
execute transactions with OCC parallelism.

## Testing performed to validate your change
Tested on sei-chain

## Describe your changes and provide context
This removes the block gas meter for occ, and will eventually be rebased
out with a corresponding change that will end up in main

## Testing performed to validate your change
loadtest cluster testing

## Describe your changes and provide context
This reduces some of the locking contention experienced when executing
transactions with OCC. Additionally, undoes an earlier revert that
reintroduced some locking for event emission

## Testing performed to validate your change

## Describe your changes and provide context

## Testing performed to validate your change

---------

Co-authored-by: Yiming Zang <[email protected]>

## Describe your changes and provide context

## Testing performed to validate your change

## Describe your changes and provide context
- **retries** represents number of tx attempts beyond the first attempt
- **max_incarnation** is the highest incarnation seen in a given block

## Testing performed to validate your change
- lower environment