Fix permission_allowed_sql_bridge to not apply defaults, closes #2526

The bridge was incorrectly using the new allowed() method which applies
default allow rules. This caused actors without restrictions to get True
instead of USE_DEFAULT, breaking backward compatibility.

Fixed by:
- Removing the code that converted to resource objects and called allowed()
- Bridge now ONLY checks config-based rules via _config_permission_rules()
- Returns None when no config rules exist, allowing Permission.default to apply
- This maintains backward compatibility with the permission_allowed() API

All 177 permission tests now pass, including test_actor_restricted_permissions
and test_permissions_checked which were previously failing.

tests/test_permissions.py

@@ -344,16 +344,13 @@ def test_query_list_respects_view_query():
                 ("execute-sql", "fixtures"),
             ],
         ),
-        pytest.param(
+        (
             "/fixtures.db",
             [
                 "view-instance",
                 ("view-database", "fixtures"),
                 ("view-database-download", "fixtures"),
             ],
-            marks=pytest.mark.xfail(
-                reason="ensure_permissions() short-circuits, not checking all permissions - see #2526"
-            ),
         ),
         (
             "/fixtures/neighborhood_search",