go/consensus/api: Add method GetBlockResults

[peternose]

Method GetBlockResults is needed by the light client node to serve events.

If performance degrades due to unmarshalling block results metadata in every GetEvents call, we can retain the backend interface and use GetCometBFTBlockResults if implemented, falling back to GetBlockResults otherwise.

[netlify]

✅ Deploy Preview for oasisprotocol-oasis-core canceled.

Name	Link
🔨 Latest commit	246a058
🔍 Latest deploy log	https://app.netlify.com/sites/oasisprotocol-oasis-core/deploys/681bd062718f3d0008525461

[codecov]

Codecov Report

Attention: Patch coverage is 63.14554% with 157 lines in your changes missing coverage. Please review.

Project coverage is 64.31%. Comparing base (5f9c3c0) to head (246a058).
Report is 8 commits behind head on master.

Files with missing lines	Patch %	Lines
go/consensus/cometbft/vault/events.go	41.37%	30 Missing and 4 partials ⚠️
go/consensus/cometbft/roothash/events.go	64.61%	16 Missing and 7 partials ⚠️
go/consensus/cometbft/staking/events.go	66.17%	16 Missing and 7 partials ⚠️
go/consensus/cometbft/api/api.go	54.05%	16 Missing and 1 partial ⚠️
go/consensus/cometbft/registry/events.go	70.00%	10 Missing and 5 partials ⚠️
go/consensus/cometbft/governance/events.go	70.21%	10 Missing and 4 partials ⚠️
go/consensus/cometbft/full/common.go	70.83%	4 Missing and 3 partials ⚠️
go/consensus/cometbft/vault/vault.go	12.50%	7 Missing ⚠️
go/consensus/api/grpc.go	64.70%	3 Missing and 3 partials ⚠️
go/consensus/cometbft/full/archive.go	25.00%	2 Missing and 1 partial ⚠️
... and 4 more

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6180      +/-   ##
==========================================
- Coverage   64.36%   64.31%   -0.05%     
==========================================
  Files         646      651       +5     
  Lines       65217    65266      +49     
==========================================
- Hits        41979    41978       -1     
- Misses      18350    18393      +43     
- Partials     4888     4895       +7     

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[kostko]

Would be good to open an issue to benchmark the difference (if any) before release.

[peternose]

Would be good to open an issue to benchmark the difference (if any) before release.

Maybe it is easier to just optimize for full nodes. See the last commit.