docs: document Articles IV, V & VI as project-customizable in spec-driven.md

spec-driven.md

@@ -318,6 +318,18 @@ No implementation code shall be written before:
 
 This completely inverts traditional AI code generation. Instead of generating code and hoping it works, the LLM must first generate comprehensive tests that define behavior, get them approved, and only then generate implementation.
 
+#### Articles IV, V & VI: Project-Specific Standards
+
+Articles IV, V, and VI are reserved for project-specific standards that teams define to suit their integration, operational, and lifecycle needs:
+
+- **Article IV** typically addresses integration concerns—such as integration testing requirements, contract testing across service boundaries, or cross-component communication standards.
+
+- **Article V** typically addresses operational concerns—such as observability, structured logging, or monitoring requirements.
+
+- **Article VI** typically addresses lifecycle concerns—such as versioning schemes, breaking-change policies, or deprecation strategies.
+
+Teams are free to name and scope these articles in whatever way best fits their project. They represent the primary customization points in the constitution where project-specific architectural principles are codified.
+
 #### Articles VII & VIII: Simplicity and Anti-Abstraction
 
 These paired articles combat over-engineering: