Make listing discovery unit-aware

skills/property-assessor/SKILL.md

@@ -17,6 +17,9 @@ Accept any of:
 The assessment purpose is required for a decision-grade result.
 If the user does not say why they want the property assessed, stop and ask before finalizing the analysis.
 
+If the property has a unit / apartment / suite number, include it.
+Do not drop the unit when discovering listing sources. Unit-qualified condo/townhome addresses must be matched as the exact unit, while single-family addresses with no unit should still work normally.
+
 ## Core workflow
 
 1. Normalize the address and property type.