CollisionDetector counted a derived template's own override row (same name as a
parent member, IsInherited=false) as a second definition alongside the
parent's row, so AddAttribute/AddAlarm/AddScript for a fresh name failed with a
false "Naming collision" once any override existed. The inheritance walk now
keeps a (type, name) shadow set: a member defined at a nearer level of the
chain shadows the same member further up (effective member set, by name),
including overrides at mid levels. Real collisions (e.g. against a composed
module) still report.
Regression tests in TemplateEngine.Tests (detector + service, attribute/alarm/
script, mid-level override, positive control); 6 fail without the fix.
The #118 importer's additions-before-overrides ordering is now unnecessary but
harmless and was left in place.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Joseph Doherty
1ccd6cfe33