fix(conversation_store,admin,cli): keep session when file lags db, sort pty by recency

src/beaver_gateway/cli.py

@@ -21,7 +21,9 @@ it just keeps the aggregator running for anyone who needs it.
 from __future__ import annotations
 
 import asyncio
+import contextlib
 import logging
+import signal
 from contextlib import AsyncExitStack
 from typing import TYPE_CHECKING
 
@@ -60,9 +62,33 @@ def main() -> None:
     logging.basicConfig(
         level=logging.INFO, format="%(asctime)s %(levelname)s %(name)s: %(message)s"
     )
+    _install_sigterm_handler()
     asyncio.run(_async_main(), loop_factory=uvloop.new_event_loop)
 
 
+def _install_sigterm_handler() -> None:
+    """Turn SIGTERM into a normal interpreter exit.
+
+    Python's default SIGTERM disposition kills the process outright, so
+    neither ``AsyncExitStack`` unwinding nor ``atexit`` hooks run. That
+    matters because every ``claude`` we spawn lives in its own session
+    (ptyprocess calls ``setsid``), which makes it immune to the signal
+    that took us down — a hard SIGTERM leaves one orphaned CLI per live
+    session, each holding hundreds of MB. Raising ``KeyboardInterrupt``
+    instead routes ``docker stop`` / ``systemctl stop`` through the same
+    shutdown path as Ctrl-C, which does reap them.
+
+    Only installed when we own the main thread's signal handlers; under
+    an embedding host that isn't ours to take.
+    """
+
+    def _raise_interrupt(_signum: int, _frame: object) -> None:
+        raise KeyboardInterrupt
+
+    with contextlib.suppress(ValueError, OSError):
+        signal.signal(signal.SIGTERM, _raise_interrupt)
+
+
 async def _async_main() -> None:
     # Populate ``os.environ`` from ``.env`` before anything else so the
     # user's ``config.py`` can read its own secrets via ``os.environ[...]``