docs: tighten perl support guidance

skills/perl-patterns/SKILL.md

@@ -16,6 +16,10 @@ Idiomatic Perl 5.36+ patterns and best practices for building robust, maintainab
 - Designing Perl module architecture
 - Migrating pre-5.36 code to modern Perl
 
+## How It Works
+
+Apply these patterns as a bias toward modern Perl 5.36+ defaults: signatures, explicit modules, focused error handling, and testable boundaries. The examples below are meant to be copied as starting points, then tightened for the actual app, dependency stack, and deployment model in front of you.
+
 ## Core Principles
 
 ### 1. Use `v5.36` Pragma