style: ruff's own fixes, mechanically applied

`ruff check .` had gone unrun long enough to report 568 errors, which is the
same as having no linter: the next real finding would have been invisible in the
noise. This is the 521 it fixes by itself, in 173 files, and nothing else — the
98 it cannot fix are the next commit.

What actually changed: import sorting (225), imports nobody used (87, none of
them a re-export — no `__init__.py` is touched, which was the one way this could
have broken an import elsewhere), `datetime.timezone.utc` to `datetime.UTC` (69)
and `asyncio.TimeoutError` to `TimeoutError` (18), both plain aliases on the 3.12
this project requires, `Optional[X]` to `X | None` (24), and f-strings with
nothing to interpolate (19).

Checked rather than assumed: every module in the three packages still imports,
and the suite is 2893 passed — the same count, test for test, as the merge
before it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/packages/meshbay-hub/tests/test_login_lockout.py b/packages/meshbay-hub/tests/test_login_lockout.py
index 6f17d98..601edbd 100644
--- a/packages/meshbay-hub/tests/test_login_lockout.py
+++ b/packages/meshbay-hub/tests/test_login_lockout.py
@@ -18,14 +18,13 @@ is `test_availability_between_members.py`, because it takes two accounts.
 """
 
 import asyncio
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 
 import pytest
-from sqlalchemy import select, update
-
 from meshbay_hub.api.deps import set_admin_usernames
 from meshbay_hub.db.models import LoginThrottle
 from meshbay_hub.login_throttle import _key
+from sqlalchemy import select, update
 
 RIGHT = "r" * 44
 WRONG = "w" * 44
@@ -94,7 +93,7 @@ async def test_a_lockout_ends_when_its_window_does(client, db_session):
 
     await db_session.execute(
         update(LoginThrottle).where(LoginThrottle.key == _key("dave_test"))
-        .values(last_failure_at=datetime.now(timezone.utc) - timedelta(minutes=61)))
+        .values(last_failure_at=datetime.now(UTC) - timedelta(minutes=61)))
     await db_session.commit()
 
     assert (await _login(client, "dave_test", RIGHT)).status_code == 200
@@ -106,7 +105,7 @@ async def test_old_failures_do_not_carry_into_a_new_window(client, db_session):
     await _fail(client, "erin_test", 3)
     await db_session.execute(
         update(LoginThrottle).where(LoginThrottle.key == _key("erin_test"))
-        .values(last_failure_at=datetime.now(timezone.utc) - timedelta(minutes=61)))
+        .values(last_failure_at=datetime.now(UTC) - timedelta(minutes=61)))
     await db_session.commit()
 
     # One stale window of three, then one fresh failure: a count of one, not four.