feat(grpc): add earliest/latest block height to GetSyncing response

[Cordtus]

Description

Ref: #15463

This PR extends the GetSyncingResponse in cosmos.base.tendermint.v1beta1.Service to include block height information that is essential for indexers and tooling.

Problem

Indexers need to know which blocks are available on a node before attempting to fetch them. Currently, this information is only available via CometBFT's /status RPC endpoint (sync_info.earliest_block_height), requiring clients to query two different endpoints.

When an indexer tries to fetch a pruned block, it gets an error like:

height 60 is not available, lowest height is 28566001

Discovering available block heights proactively via gRPC would be more efficient.

Solution

Add two new fields to GetSyncingResponse:

• earliest_block_height - The earliest block height available on this node
• latest_block_height - The latest block height available on this node

These fields expose the same information as CometBFT's SyncInfo struct, making it available via the existing gRPC endpoint without requiring a separate RPC call.

Changes

File	Change
proto/cosmos/base/tendermint/v1beta1/query.proto	Add new fields to GetSyncingResponse
client/grpc/cmtservice/query.pb.go	Generated code with new fields
client/grpc/cmtservice/service.go	Populate new fields from SyncInfo
tests/systemtests/cometbft_service_test.go	Add systemtest with pruning verification

API

message GetSyncingResponse {
  bool syncing = 1;
  int64 earliest_block_height = 2;  // NEW
  int64 latest_block_height = 3;    // NEW
}

Testing

Systemtest added (TestCometBFTGetSyncingGRPC and TestCometBFTGetSyncingWithBlockRetention) that:

1. Verifies gRPC endpoint returns valid block heights
2. Confirms latest_block_height increases over time
3. Confirms earliest_block_height is stable on unpruned chains
4. Verifies pruning behavior: Configures min-retain-blocks=5 and max_age_num_blocks=5 (in genesis), then confirms earliest_block_height increases as blocks are pruned

The pruning test required modifying both app.toml (via EditToml) and genesis params (via ModifyGenesisJSON) because CometBFT's block retention is the minimum of min-retain-blocks and max_age_num_blocks. Default max_age_num_blocks=100000 would prevent pruning in tests.

=== RUN   TestCometBFTGetSyncingWithBlockRetention
    Initial state: earliest=1, latest=5
    Waiting for 15 blocks to trigger block pruning (minRetainBlocks=5)...
    After 15 blocks: earliest=15, latest=20
    Block range: 5 (latest 20 - earliest 15)
--- PASS: TestCometBFTGetSyncingWithBlockRetention (56.35s)

Backward Compatibility

This is a non-breaking change - it only adds new optional fields to an existing response message. Existing clients will continue to work unchanged.

Use Case

// Before: Need to query CometBFT RPC separately
status, _ := rpcClient.Status(ctx)
earliest := status.SyncInfo.EarliestBlockHeight

// After: Available via gRPC
resp, _ := cmtClient.GetSyncing(ctx, &GetSyncingRequest{})
earliest := resp.EarliestBlockHeight

[fmorency]

This would be useful for manifest-network/yaci#28

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 68.20%. Comparing base (1bb329d) to head (551eec6).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #25648      +/-   ##
==========================================
+ Coverage   66.50%   68.20%   +1.69%     
==========================================
  Files         929      894      -35     
  Lines       60231    58146    -2085     
==========================================
- Hits        40058    39658     -400     
+ Misses      20173    18488    -1685     

Files with missing lines	Coverage Δ
client/grpc/cmtservice/service.go	84.05% <100.00%> (+0.23%)	⬆️

... and 38 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Cordtus]

Added a systemtest. Run with:

cd tests/systemtests && go test -tags='system_test' -v --run 'TestCometBFT' --wait-time=120s --nodes-count=1

The pruning test configures min-retain-blocks=5 in app.toml and max_age_num_blocks=5 in genesis (Comet block retention uses the minimum of both), waits 15 blocks, then confirms earliest_block_height increases from 1 to 15 as blocks get pruned.

[fmorency]

@aljo242 is there anything blocking this PR?

[Cordtus]

Bump. Would like to be sure there is nothing else needed from my end here.

[aljo242]

@technicallyty to review this

[technicallyty]

LGTM

[technicallyty]

needs go mod tidy and changelog

[aljo242]

@Cordtus looks like you need to run make mocks

[Cordtus]

@aljo242 @technicallyty -- could the backport/v0.53.x label be added here as well? This was merged to main but didn't make it into v0.53.6. Would be great to have in the next patch release. Thanks!

[technicallyty]

@mergify backport release/v0.53.x

[mergify]

backport release/v0.53.x

✅ Backports have been created

Details

• #25902 feat(grpc): add earliest/latest block height to GetSyncing response (backport #25648) has been created for branch release/v0.53.x but encountered conflicts

Cherry-pick of 174b2e9 has failed:

On branch mergify/bp/release/v0.53.x/pr-25648
Your branch is up to date with 'origin/release/v0.53.x'.

You are currently cherry-picking commit 174b2e936.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   client/grpc/cmtservice/query.pb.go
	modified:   client/grpc/cmtservice/service.go
	new file:   client/grpc/cmtservice/service_test.go
	modified:   proto/cosmos/base/tendermint/v1beta1/query.proto
	new file:   tests/systemtests/cometbft_service_test.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   CHANGELOG.md
	both modified:   go.mod
	both modified:   go.sum
	both modified:   tests/systemtests/go.mod

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally