Add handlers for supported synthesis events for Azure TTS

[anishnag]

Adding handlers for each of the SpeechSynthesizer subscribable events according to the docs:

• BookmarkReached
• SynthesisCanceled
• SynthesisCompleted
• SynthesisStarted
• Synthesizing
• VisemeReceived
• WordBoundary

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Latest commit: 2572a17

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

This PR includes changesets to release 1 package

Name	Type
livekit-plugins-azure	Patch

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[theomonnom]

Hey, can you fix the Ruff CI.

Also curious, why do you need those callbacks? It seems hard to correlate them with the ChunkedStream output (Since the frames will be read asynchronously)

[anishnag]

Hey, can you fix the Ruff CI.

Also curious, why do you need those callbacks? It seems hard to correlate them with the ChunkedStream output (Since the frames will be read asynchronously)

@theomonnom For now, we do client-side syncing given these events. Eventually we'll want to make it work on the agent side which would probably look like monitoring the audio frames and relaying the events based on running duration.