style: apply ruff format across backend + scripts (line-length 100)

Mechanical, whole-tree `ruff format` pass — no behaviour change. Recorded in
.git-blame-ignore-revs (next commit) so git blame skips it.

backend/tests/test_config_commit_ownership.py

@@ -3,6 +3,7 @@ transaction and a change lands together with its audit row. These lock that cont
 before the caller commits discards the change (proving no hidden internal commit), while a same-session
 read still sees it (flush visibility). DB lane (`db` fixture) — skipped without Postgres.
 """
+
 from app import state, sysconfig
 
 
@@ -14,7 +15,9 @@ def test_set_value_flushes_but_leaves_the_commit_to_the_caller(db):
     assert sysconfig.get_int(db, "quota_daily_budget") == new  # visible in-session (flushed)
 
     db.rollback()  # the caller never committed
-    assert sysconfig.get_int(db, "quota_daily_budget") == default  # discarded — no hidden self-commit
+    assert (
+        sysconfig.get_int(db, "quota_daily_budget") == default
+    )  # discarded — no hidden self-commit
 
 
 def test_reset_flushes_but_leaves_the_commit_to_the_caller(db):
@@ -25,7 +28,9 @@ def test_reset_flushes_but_leaves_the_commit_to_the_caller(db):
     sysconfig.reset(db, "quota_daily_budget")
     assert sysconfig.get_int(db, "quota_daily_budget") == default  # reset visible in-session
     db.rollback()
-    assert sysconfig.get_int(db, "quota_daily_budget") == default + 10  # reset discarded until committed
+    assert (
+        sysconfig.get_int(db, "quota_daily_budget") == default + 10
+    )  # reset discarded until committed
 
 
 def test_set_sync_paused_flushes_but_leaves_the_commit_to_the_caller(db):