Clean up consensus etcd log output

Integrates our Zap logger into our etcd embedded instance to
clean up the logs. Split out from D497 (ex feature/kubelet).

Test Plan:
`bazel run //core/scripts:launch` no longer shows etcd JSON
output.

X-Origin-Diff: phab/D498
GitOrigin-RevId: 8df3b9c3edd20310079306479adfadf983af7da2
diff --git a/core/internal/consensus/consensus.go b/core/internal/consensus/consensus.go
index 77a8a11..67bac1c 100644
--- a/core/internal/consensus/consensus.go
+++ b/core/internal/consensus/consensus.go
@@ -46,6 +46,7 @@
 	"go.etcd.io/etcd/pkg/types"
 	"go.etcd.io/etcd/proxy/grpcproxy/adapter"
 	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
 	"golang.org/x/sys/unix"
 
 	"git.monogon.dev/source/nexantic.git/core/internal/consensus/ca"
@@ -172,6 +173,11 @@
 	}
 
 	cfg.Logger = DefaultLogger
+	cfg.ZapLoggerBuilder = embed.NewZapCoreLoggerBuilder(
+		s.Logger.With(zap.String("component", "etcd")).WithOptions(zap.IncreaseLevel(zapcore.WarnLevel)),
+		s.Logger.Core(),
+		nil,
+	)
 
 	server, err := embed.StartEtcd(cfg)
 	if err != nil {