feat: improve performance BTC reward distribution

[RafilxTenfen]

• Add new structures to track BTC delegation rewards and lazily distribute
• Add new event BTCDelegationStatus_EXPIRED for BTC delegations that indicates a BTC delegation is no longer contributing to security
• Important files diff for review
  • proto/babylon/incentive/rewards.proto
  • x/finality/keeper/power_dist_change.go
  • x/incentive/keeper/btc_staking_gauge.go
  • x/incentive/keeper/grpc_query.go
  • x/incentive/keeper/msg_server.go
  • x/incentive/keeper/reward_tracker.go
  • x/incentive/keeper/reward_tracker_store.go
  • x/btcstaking/keeper/btc_delegations.go
  • x/btcstaking/keeper/msg_server.go
  • x/btcstaking/types/btc_delegation.go

Benchmarks

Command to generate pprof go tool pprof -http=:8080 http://localhost:6060/debug/pprof/profile\?seconds\=300

• Main branch that iterates over delegations to distribute rewards with 163k BTC delegations, took 15.52s (13.1%) of the time during the 300seconds interval used to generate the pprof

• Current branch rafilx/improve-performance-btc-dist with 100k BTC delegations, took 6.73s (1.8%) of the time during the 300seconds interval

Note that the percentage of the time used that is ~7x lower should be considered instead of the time, the benchmark from main was running in the benchmark server 48 processors and 256GB of RAM while the one in the current branch I run locally with 24 processors and 96GB of RAM.... So the percentage of the time usage instead of seconds should be the one in comparison

Thanks @Lazar955 for help with benchmark
The function used to show the difference is the TallyBlocks because the RewardBTCStaking does not appear in the pprof of the current branch demonstrating that the time spent there is negligible to the overall period

[KonradStaniec]

looks good to me 👍 great work pushing it forward :)

Lets wait for at leas one more approval before merging given size of the pr :)

[RafilxTenfen]

@SebastianElvis @gitferry Addressed all the comments 🚀

[gitferry]

Great work on the improvement! Some minor comments, no blocker:

[Lazar955]

Amazing work!