bug(ws): KalshiWebSocket._start() silently clobbers managers on repeat/nested connect() #297

import asyncio
from kalshi import KalshiAuth, KalshiConfig
from kalshi.ws import KalshiWebSocket

async def main():
    auth = KalshiAuth.from_key_path("kid", "key.pem")
    ws = KalshiWebSocket(auth=auth, config=KalshiConfig.demo())

    # Pattern 1: accidental nested re-entry (e.g. helper function picked up a
    # cached `ws` from outer scope)
    async with ws.connect() as outer:
        stream_a = await outer.subscribe_ticker(tickers=["AAA"])
        async with ws.connect() as inner:  # ← silently clobbers outer's state
            stream_b = await inner.subscribe_ticker(tickers=["BBB"])
            # stream_a is now orphaned — its sid is no longer in the new sub_mgr
        # outer.__aexit__ closes the freshly-replaced connection; stream_a never
        # exits its `async for` (no sentinel was put on the orphaned queue).

async def _start(self) -> None:
    """Connect and initialize managers. Does NOT start recv_loop yet."""
    if self._connection is not None or self._running:
        raise RuntimeError(
            "KalshiWebSocket session is already started. Each WS instance "
            "supports exactly one active session — create a new "
            "KalshiWebSocket() for a new session, or exit the existing "
            "`async with ws.connect()` first."
        )
    self._connection = ConnectionManager(...)
    ...

async def test_double_start_raises(test_auth, config):
    ws = KalshiWebSocket(auth=test_auth, config=config)
    async with ws.connect():
        with pytest.raises(RuntimeError, match="already started"):
            async with ws.connect():
                pass