relax websockets upper bound from <16 to <17

[mathisobadia]

Summary

The `websockets<16` upper bound introduced in 0.14.0 is overly conservative. websockets 16.0 has no breaking changes that affect this SDK, and the cap is creating unnecessary dependency conflicts for projects already on `websockets==16.x`.

Analysis

APIs used by this SDK

All websockets usage is in `src/agents/realtime/openai_realtime.py` and `src/agents/voice/`:

API	Import path
`connect()`	`websockets.connect` and `websockets.asyncio.client`
`ClientConnection`	`websockets.ClientConnection` and `websockets.asyncio.client.ClientConnection`
`ConnectionClosed`	`websockets.exceptions.ConnectionClosed` and `websockets.ConnectionClosed`
`ConnectionClosedOK`	`websockets.exceptions.ConnectionClosedOK`
`ConnectionClosedError`	`websockets.exceptions.ConnectionClosedError`

websockets 16.0 breaking changes

From the official changelog, websockets 16.0 has one backwards-incompatible change:

websockets 16.0 requires Python ≥ 3.10. websockets 15.0 is the last version supporting Python 3.9.

`openai-agents` already declares `requires-python = ">=3.10"`, so this does not apply.

Every API listed above is present in websockets 16.0 with identical module paths and method signatures — confirmed against the 16.0 source.

Test compatibility

The existing test suite requires zero changes to run against websockets 16.0:

• The mock-based tests (`patch("websockets.connect", ...)`) are duck-typed and don't rely on any websockets internals
• The real integration tests in `TestTransportIntegration` (which spin up a real local WebSocket server via `websockets.serve`) use only APIs that are identical in 16.x
• The `ClientConnection.close_code` attribute used in integration test assertions is present and unchanged in 16.0

Changes

• 3 lines in `pyproject.toml` (`dependencies`, `voice` extra, `realtime` extra): `<16` → `<17`
• Regenerated `uv.lock`
• New CI job `tests-websockets-v16` that explicitly installs `websockets==16.0` and runs the full `tests/realtime/` and `tests/voice/` suites to prove compatibility

Impact

Projects pinned to `websockets==16.x` currently cannot adopt `openai-agents>=0.14.0` without a global websockets downgrade. This change unblocks them.

[seratch]

We don't want to add this additional test just for this dependency version range

[mathisobadia]

Yes that make total sense, will remove the commit, I wanted to have a way to "prove" it works with version 16