chore: drop no-op _framerate=15 patch on avatar video track

[aliev]

The avatar._sync.video_track._framerate = 15 line was reasoned to halve VP8 encode rate by slowing next_timestamp() pacing on aiortc's VideoStreamTrack. In practice it does nothing for output rate.

Agent._prepare_rtc() wraps our track in a VideoForwarder with fps=30 hardcoded:

forwarder = VideoForwarder(
    self._video_track,
    max_buffer=30,
    fps=30,  # drives consumer poll rate
    ...
)

The forwarder pulls from our track at 30 Hz. With _framerate=15 the underlying track simply returns the same frame twice in a row; the forwarder still emits 30 fps and the encoder still runs at 30 fps, just on duplicate input. CPU savings are effectively zero, and the absence of visible 15 fps lag in earlier load tests confirmed nothing about the output was actually capped.

AVSynchronizer.fps doesn't help either — it controls _pending release timing, not consumer poll rate, so the forwarder's 30 fps poll dominates.

What stays

tts=inworld.TTS(..., sample_rate=24000) is unchanged — that one is verified working (live memory drop measured after deploy when Inworld stopped emitting 16kHz that needed in-loop resampling to 24kHz).

Followup

If we want to actually cap the outbound encode rate, the lever is the VideoForwarder's fps argument, not the underlying track. That's deeper in framework territory and not worth doing for this demo.

[vercel]

@aliev must be a member of the GetStreamio team on Vercel to deploy.
- Click here to add @aliev to the team.
- If you initiated this build, request access.

Learn more about collaboration on Vercel and other options here.