[reconciler] Performance Overhaul

[patrick-ogrady]

Related: https://github.com/coinbase/rosetta-sdk-go/tree/patrick/priority-lock

This PR introduces performance optimizations in the reconciler that reduce lock contention in the syncing loop. This PR also migrates BalanceStorage, BlockStorage, and CoinStorage to use github.com/neilotoole/errgroup (in practice, significantly reduces memory usage without impacting performance).

Changes

reconciler

• introduce utils.ShardedMap to track currently used accounts
• update tests
  • fix failing test where context.Canceled returned instead of reconciliation fails
• make enqueuing block changes async

statefulsyncer

• change statefulsyncer default pruning frequency to 10 minutes

storage

• explicitly set errgroup limit with runtime.NumCPU
• ensure BlockStorage is not using a global database transaction
• migrate BlockStorage to use github.com/neilotoole/errgroup
• migrate CoinStorage to use github.com/neilotoole/errgroup

[coveralls]

Pull Request Test Coverage Report for Build 12826

• 76 of 88 (86.36%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.05%) to 78.183%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
reconciler/reconciler.go	63	75	84.0%

Totals
Change from base Build 12702:	0.05%
Covered Lines:	7891
Relevant Lines:	10093

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💛 - Coveralls

[sidhujag]

we are able to sync our node now with official SDK, I will retest again with these changes but so far so good, memory being held in check as well. (We have increased ours due to the database change size issue but can play around there once these changes are in)

[yfl92]

LGTM