feat(streaming): add speakerLabelsRevisionIntervalMs param

[dlange-aai]

Summary

Adds speakerLabelsRevisionIntervalMs to StreamingTranscriberParams, sent as the speaker_labels_revision_interval_ms query param. That is the canonical GA name since DeepLearning#20528; the server still accepts the _-prefixed spelling as a legacy alias, but the SDK sends the GA form.

client.streaming.transcriber({
  speechModel: "universal-3-5-pro",
  sampleRate: 16_000,
  speakerLabels: true,
  speakerLabelsRevisionIntervalMs: 120_000,
});

How the server treats it (from ConnectionParameters in the realtime api_v2 gateway):

• It sets how often, in ms of audio time, the server emits mid-stream speakerRevision events. Unset or 0 gives only the end-of-stream revision; 0 is sent explicitly rather than dropped.
• Non-zero values are clamped server-side to 120 000–300 000 ms. The server rejects values below 0 or above 86 400 000 at connect. The SDK has no client-side range check, consistent with maxSpeakers.
• Only used when speakerLabels is enabled.
• The first mid-stream revision needs ~120 s of streamed speech, and a revision is sent only when some earlier turn's label changed.

Version bumped to 4.41.5 with a changelog entry, and the CLAUDE.md speaker-revisions section is updated.

Test plan

• Unit tests: the connection URL includes speaker_labels_revision_interval_ms=120000, and =0 when explicitly set to 0
• eslint, tsc and prettier are clean
• Live on prod (main diarization lane), GA param name: two parallel 240 s real-time sessions over the same audio

arm	mid-stream revisions	end-of-stream
speakerLabelsRevisionIntervalMs: 120_000	1 (at 122.7 s)	1
unset (control)	0	1

(An earlier run using the legacy _-prefixed name and a 60 000 value showed the same pattern, with its mid-stream revision at 126.3 s. The server clamps 60 000 up to 120 000.)

Note: tests/unit/utils.test.ts has 3 failures on Node 24 that also occur on clean main. They expect a runtime_env segment in the user-agent string, and are unrelated to this change.

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