test: the peer cache in the stale-disk warm test carries the peer token

[szibis]

Summary

TestLabelSurface_LabelValuesIndexStartupWarmsFromPeersWhenDiskStale failed once in release validation with unexpected peer token header: got "".

The test gives the proxy PeerAuthToken: "shared-secret" but builds the peer cache without AuthToken. Requests the proxy sends itself carry the token. Requests the peer cache sends on its own (a get or push for a key that the fake peer owns on the hash ring) did not. Ownership depends on the random httptest port, so the test failed only sometimes.

cmd/proxy sets the same token on both (cache.PeerConfig.AuthToken: cfg.peerAuthToken). The test now does the same. Test-only change; no behaviour change.

Test plan

• go test -short -p 1 -race -count=50 -run TestLabelSurface_LabelValuesIndexStartupWarms ./internal/proxy/ passes

[github-actions]

PR Quality Report

Compared against base branch main.

Coverage and tests

Signal	Base	PR	Delta
Test count	10738	10738	0
Coverage	88.0%	88.0%	0.0% (stable)

Compatibility

Track	Base	PR	Delta
Loki API	100.0%	11/11 (100.0%)	0.0% (stable)
Logs Drilldown	100.0%	17/17 (100.0%)	0.0% (stable)
VictoriaLogs	100.0%	11/11 (100.0%)	0.0% (stable)

Performance smoke

Lower CPU cost (ns/op) is better. Lower benchmark memory cost (B/op, allocs/op) is better. Higher throughput is better. Lower load-test memory growth is better. Benchmark rows are medians from repeated samples.

Signal	Base	PR	Delta
QueryRange cache-hit CPU cost	2537.0 ns/op	2533.0 ns/op	-0.2% (stable)
QueryRange cache-hit memory	1240.0 B/op	1240.0 B/op	0.0% (stable)
QueryRange cache-hit allocations	27.0 allocs/op	27.0 allocs/op	0.0% (stable)
QueryRange cache-bypass CPU cost	2979.0 ns/op	2976.0 ns/op	-0.1% (stable)
QueryRange cache-bypass memory	1289.0 B/op	1289.0 B/op	0.0% (stable)
QueryRange cache-bypass allocations	27.0 allocs/op	27.0 allocs/op	0.0% (stable)
Labels cache-hit CPU cost	671.1 ns/op	671.7 ns/op	+0.1% (stable)
Labels cache-hit memory	48.0 B/op	48.0 B/op	0.0% (stable)
Labels cache-hit allocations	3.0 allocs/op	3.0 allocs/op	0.0% (stable)
Labels cache-bypass CPU cost	1113.0 ns/op	1095.0 ns/op	-1.6% (stable)
Labels cache-bypass memory	397.0 B/op	397.0 B/op	0.0% (stable)
Labels cache-bypass allocations	14.0 allocs/op	14.0 allocs/op	0.0% (stable)

State

• Coverage, compatibility, and sampled performance are reported here from the same PR workflow.
• This is a delta report, not a release gate by itself. Required checks still decide merge safety.
• Performance is a smoke comparison, not a full benchmark lab run.
• Delta states use the same noise guards as the quality gate (percent + absolute + low-baseline checks), so report labels match merge-gate behavior.