test(backup): run 9076's three failures (#5673, #5674)

- The audit-wording guard now reads both branches of a conditional action
  ("backup.made" if ok else "backup.failed"), and its self-test covers that.
- The Backups save test no longer asserts the session's tz, which sign-in
  state sets, not the test.
- The restore integration test uses the app's own metadata. all_metadata
  without plugin dirs imports the `plugins` package as the tests do; loading
  by path under the loader's names is only for `steward restore`. Loading by
  path in the shared test process had mapped traefik and unifi tables a
  second time for later tests.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/integration/test_backup_restore_fixes.py

@@ -23,7 +23,8 @@ def app():
 def test_a_dangling_ansible_run_link_is_cleared_and_the_event_kept(app):
     from sqlalchemy import select, text
 
-    from steward.backup.restore import _execute, all_metadata, dangling_fixes
+    from steward.backup.restore import _execute, dangling_fixes
+    from steward.models.base import Base
     from steward.models.alerts import AlertEvent, AlertOperator, AlertRule
     from steward.models.users import User, UserRole
 
@@ -49,7 +50,7 @@ def test_a_dangling_ansible_run_link_is_cleared_and_the_event_kept(app):
                 s.add(AlertEvent(id=plain, rule_id=rule_id, from_state="firing",
                                  to_state="inactive"))
 
-        fixed = await _execute(os.environ["STEWARD_DATABASE_URL"], dangling_fixes(all_metadata()))
+        fixed = await _execute(os.environ["STEWARD_DATABASE_URL"], dangling_fixes(Base.metadata))
 
         async with app.db_sessionmaker() as s:
             rows = dict((await s.execute(