FastItemLevel.11.6

Avoid stringifying GUIDs and stop comparing secret tooltip GUIDs; store unit token with pending inspects and invoke callbacks from that entry. Resolve units from tooltip via tooltipData.unitToken or tooltip:GetUnit() (with safe UnitExists checks) and fall back to mouseover. Update INSPECT_READY flow to use the stored unit (and skip stale/nonexistent units) and call pending.callback. Also bump addon version to 11.6.