* Validator improvements
* Fix cancelling state serialization
* Disable state serializer on all mainnet validators
* Flag --catchain-max-block-delay-slow
* Set default catchain-max-block-delay to 0.4, delay-slow to 1.0
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Co-authored-by: SpyCheese <mikle98@yandex.ru>
This commit contains some parts of https://github.com/ton-blockchain/ton/tree/accelerator
This is auxiliary code that mostly does not change node behavior.
1) Semiprivate overlays and other improvements in overlays code
2) Rename actual_min_split -> monitor_min_split, fix building shard overlays
3) Loading block candidates by block id from DB, fix accept_block after validator restart
4) Cells: ProofStorageStat and changes in CellUsageTree
5) Remove some unused code, other minor changes
* Fix double serialization of masterchain; increase sync_blocks_before
* Improve logging in DownloadState
* Write persistent state directly to file instead of a buffer
* Don't keep ref to masterchain state in AsyncStateSerializer
* Sparse state serialization over longer period
Co-authored-by: SpyCheese <mikle98@yandex.ru>
