fix(replay): stream each case's output and survive a deadline overrun

The 13.3 replay on 7cf256b crashed on case 1: `pre-push` ran past its
7,200 s deadline plus the harness's 60 s grace, `subprocess.run` raised
TimeoutExpired, the harness died without running cases 2 and 3, and the
case's captured output died with it. Each case now streams stdout and
stderr to files with INFO logging on; an overrun kills the case's process
group, is recorded as `deadline_overrun` with its size -- the product
failing its cancellation contract -- and the next case still runs.
`--only` reruns selected cases. CLI log lines now carry a timestamp, so a
log can say where the time went.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo

src/openultrasast/cli.py

@@ -116,7 +116,7 @@ def _configure_logging() -> None:
     if level not in {"DEBUG", "INFO", "WARNING", "ERROR"}:
         return
     handler = logging.StreamHandler()
-    handler.setFormatter(logging.Formatter("%(levelname)s %(name)s %(message)s"))
+    handler.setFormatter(logging.Formatter("%(asctime)s %(levelname)s %(name)s %(message)s", "%H:%M:%S"))
     root = logging.getLogger("openultrasast")
     root.handlers = [handler]
     root.setLevel(getattr(logging, level))