Update templates

templates/spec-template.md

@@ -55,3 +55,17 @@
 
 - **[Entity 1]**: [What it represents, key attributes without implementation]
 - **[Entity 2]**: [What it represents, relationships to other entities]
+
+## Success Criteria *(mandatory)*
+
+<!--
+  ACTION REQUIRED: Define measurable success criteria.
+  These must be technology-agnostic and measurable.
+-->
+
+### Measurable Outcomes
+
+- **SC-001**: [Measurable metric, e.g., "Users can complete account creation in under 2 minutes"]
+- **SC-002**: [Measurable metric, e.g., "System handles 1000 concurrent users without degradation"]
+- **SC-003**: [User satisfaction metric, e.g., "90% of users successfully complete primary task on first attempt"]
+- **SC-004**: [Business metric, e.g., "Reduce support tickets related to [X] by 50%"]