Bundle realtime initial state into livekit_join

[VerioN1]

Summary

• Bring Android realtime signaling to parity with feat(realtime): bundle initial_state into livekit_join sdk#155 by bundling the first prompt/set_image payload into livekit_join.initial_state.
• Buffer early prompt_ack / set_image_ack messages until the post-livekit_room_info waiter consumes them, keeping ack timeout timing after room info.
• Preserve the post-room-info setImage / sendPrompt path for legacy two-step updates.

Test plan

• ./gradlew :sdk:testDebugUnitTest

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Note

Medium Risk
Changes the realtime connect handshake and ack timing on a critical path; mitigated by buffered early acks, unchanged legacy setImage/sendPrompt, and unit tests, but still depends on server support for initial_state.

Overview
Bundles the first prompt / set_image payload into livekit_join.initial_state instead of sending separate client messages after join, aligning Android realtime signaling with the cross-SDK change.

RealtimeSessionManager passes initialState into sendLiveKitJoin and only awaits the matching ack via awaitInitialStateAck (no duplicate sends). SignalingChannel replaces SharedFlow ack listeners with a waiter/buffer model so prompt_ack / set_image_ack that arrive before livekit_room_info are held until the post–room-info waiter runs; post-connect setImage / sendPrompt still send on the wire. Wire format updates: LiveKitJoinMessage carries nested initial_state; serialization tests and new SignalingChannelTest cover bundled join, early ack buffering, and the legacy path.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Buffered acks ignore new waiters

High Severity

awaitAckMessage only scans bufferedAcks before registering a waiter. If a matching ack arrives on the WebSocket thread in that gap (or is dropped when connected is already true), it never pairs with the waiter, so bundled initial-state or legacy setImage/sendPrompt calls can time out despite a successful server ack and fail the session connect.

Additional Locations (1)

• sdk/src/main/java/ai/decart/sdk/realtime/SignalingChannel.kt#L424-L432

 

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