Widen the stdio round-trip test's termination grace and overall timeout

The test patches PROCESS_TERMINATION_TIMEOUT so the spawned server can
unwind, save its subprocess coverage data, and print the clean-exit line
before the kill escalation. One heavily starved Windows CI runner stalled
the child past the previous 10s grace, so it was killed before printing and
the stderr assertion failed with empty output. The post-stdin-close tail is
normally well under a second even on loaded Windows runners, so double the
grace to 20s (and the outer fail_after to 30s); the grace wait returns as
soon as the child exits, so passing runs are unaffected.

Author: maxisbey

tests/interaction/transports/test_stdio.py

@@ -61,8 +61,10 @@ async def test_tool_call_and_notification_round_trip_over_a_stdio_subprocess(
     # post-print kill can no longer silently lose the data file -- see _stdio_server.main). The
     # production 2s default is too tight for the unwind+save tail on loaded Windows runners
     # (measured in-situ p99 of the whole test is ~7s); a kill before the print fails the stderr
-    # assertion below loudly rather than tripping the coverage gate. Not under test.
-    monkeypatch.setattr(stdio, "PROCESS_TERMINATION_TIMEOUT", 10.0)
+    # assertion below loudly rather than tripping the coverage gate. The 20s grace covers even a
+    # badly starved runner (a >10s stall has been seen once in CI) and costs nothing when the
+    # child exits promptly. Not under test.
+    monkeypatch.setattr(stdio, "PROCESS_TERMINATION_TIMEOUT", 20.0)
 
     received: list[LoggingMessageNotificationParams] = []
 
@@ -85,8 +87,8 @@ async def collect(params: LoggingMessageNotificationParams) -> None:
             errlog=errlog,
         )
 
-        # Must exceed session time plus the patched PROCESS_TERMINATION_TIMEOUT (10s).
-        with anyio.fail_after(20):
+        # Must exceed session time plus the patched PROCESS_TERMINATION_TIMEOUT (20s).
+        with anyio.fail_after(30):
             async with Client(transport, logging_callback=collect) as client:
                 assert client.initialize_result.server_info.name == "stdio-echo"
                 result = await client.call_tool("echo", {"text": "across\nprocesses"})