fix(sarvam, simplismart): close the streams the STT collects

[Rehansanjay]

Found by reading the plugins rather than from a report, so there is no issue to close.

The leak

Both sarvam and simplismart give every stream its own aiohttp session:

# Create a fresh session for this stream to avoid conflicts
stream_session = aiohttp.ClientSession()

and only SpeechStream.aclose() closes it (simplismart at line 428, sarvam at 1100).

Both also collect their streams:

self._streams = weakref.WeakSet[SpeechStream]()
...
self._streams.add(stream)

But neither STT class defines aclose(). In sarvam/stt.py the only aclose in the file belongs to SpeechStream (line 1056, with class SpeechStream at 868); simplismart is the same shape. So STT.aclose() resolves to the abstract no-op on the base class, those streams are never closed, and their sessions stay open — aiohttp reports unclosed client sessions and the sockets survive until the objects happen to be collected.

Why this reads as an omission rather than a decision

The WeakSet is the tell. In both files it is initialised, added to, and then never read again — the shape of cleanup that was intended and not written. I checked every plugin that keeps a _streams set, and these two are the only ones where nothing reads it.

Everywhere else it is read:

• cartesia, palabra, telnyx — close through it in aclose
• rime (TTS) — for s in list(self._streams): await s.aclose()
• sarvam's own stt_streaming.py — already has this exact method at line 466, a few hundred lines from the file this PR touches
• the STT plugins that don't close through it (deepgram, assemblyai, azure, …) read it to propagate update_options

The base contract asks for it as well — STT.aclose is documented as "Close the STT, and every stream/requests associated with it".

The change

Eleven lines in each plugin, mirroring stt_streaming.py:

async def aclose(self) -> None:
    for stream in list(self._streams):
        await stream.aclose()
    self._streams.clear()

Neither STT owns a session of its own to close — sarvam resolves through utils.http_context.http_session() — so the streams are the whole of it.

Verification, and its limits

ruff check and ruff format --check pass on both files at the repo's line-length = 100 / target-version = py310, and both compile.

Being straight about what I did not do: I have not run the test suite locally, and there is no test in this PR. The correctness argument here is that stream() creates a session, only SpeechStream.aclose() closes it, and nothing was calling it — plus five existing implementations of the same method in this repo to match. If you would like a regression test, tell me where it belongs and I will add one.

[CLAassistant]

All committers have signed the CLA.

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.

[Rehansanjay]

recheck