logger: replace WithTap with WithTee

[paulwe]

WithTap took a WriteSyncer, so a tap could only ever receive bytes encoded by a zaputil-chosen encoder — Encoder.Core took two destinations, and DevelopmentEncoder carried a second JSON encoder that existed only to format tap output. WithTee hands the duplicate stream a zapcore.Core instead, built per derived logger from that logger's resolved enabler, so it brings its own encoder and sees the structured entry.

Four commits, each green on its own:

1. replay deferred writes through Check — Deferrer.write/flush called the wrapped core's Write directly. zapcore.multiCore.Write fans out to every child unconditionally, so a destination that filters in Check rather than in Write received entries it never enabled. encoderCore was immune because it re-checks each out's level inside Write; nothing else is, including zaptest/observer.
2. replace WithTap with WithTee — the API change, plus allocation benchmarks.
3. replace encoderCore with zapcore.NewCore — with one destination per core, encoderCore is ioCore plus the write-time level check that commit 1 made redundant.
4. drop the Encoder type parameter — both encoders are now one encoder and one destination, so the interface and its two implementations collapse.

Level semantics

A tee shares the console's resolved level and cannot widen what the logger emits. That is what lets the component leveler drop its OrLevelEnabler and the levelEnablers cache go away entirely.

Allocations

WithValues/WithDeferredValues run per participant and track, so logger/logger_bench_test.go covers objects allocated on both, with and without a tee. Every no-tee path is flat or better than before:

	before	after
WithValues console	18	10
WithValues json	11	10
WithDeferredValues console	14	9
WithDeferredValues json	10	9
deferred write, console	10	9
deferred flush, console	30	24
plain writes	8 / 4 / 1	unchanged

Console mode gains most: dropping DevelopmentEncoder's second encoder removes a Clone() per derivation and a core plus a NewTee slice per makeZap. Commit 1 also stopped the deferred path encoding every entry to JSON for the discard tap before throwing it away (−1 alloc, ~12% off dev-mode deferred writes).

Breaking

Removes logger.WithTap, zaputil.NewDiscardWriteEnabler, zaputil.NewEncoderCore, and zaputil.Encoder[T]/DevelopmentEncoder/ProductionEncoder as distinct types. Minor changeset included. Known downstream caller: cloud-protocol/audit_test.go, a one-line swap — it asserts WithValues fields on the tap, so it is also the live check that a tee accumulates them.

Note

Overlaps #1788, which also touches makeZap/WithMinLevel.

[changeset-bot]

🦋 Changeset detected

Latest commit: 613798c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
github.com/livekit/protocol	Minor
@livekit/protocol	Minor

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[cnderrauber]

Looks good! Will wait for this PR to land