Apply ruff formatting and fix unused import linting errors

Remove unused imports flagged by ruff (F401), apply ruff format across all
files, and restore members.signals side-effect import with noqa: F401 so the
post_save signal that auto-creates Member profiles continues to fire.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

members/filters.py

@@ -8,10 +8,18 @@ class MemberFilter(django_filters.FilterSet):
     user__first_name = django_filters.CharFilter(field_name="user__first_name", label=_("First name"), lookup_expr="icontains")
     user__last_name = django_filters.CharFilter(field_name="user__last_name", label=_("Last name"), lookup_expr="icontains")
     license = django_filters.CharFilter(label=_("License"), lookup_expr="icontains")
-    user__is_active = django_filters.TypedChoiceFilter( field_name='user__is_active', label=_("Active?"), initial="true", choices=( ('', 'All users'), ('true', 'Active users'), ('false', 'Inactive users'), ), coerce=lambda x: x.lower() == 'true' )
-    
+    user__is_active = django_filters.TypedChoiceFilter(
+        field_name="user__is_active",
+        label=_("Active?"),
+        initial="true",
+        choices=(
+            ("", "All users"),
+            ("true", "Active users"),
+            ("false", "Inactive users"),
+        ),
+        coerce=lambda x: x.lower() == "true",
+    )
+
     class Meta:
         model = Member
         fields = ["user__first_name", "user__last_name", "license", "user__is_active"]
-        
-