fix: add origin metadata to skills for traceability

Add origin field to all skill files to track their source repository.
This enables users to identify where distributed skills originated from.
Fixes affaan-m/everything-claude-code#246

skills/regex-vs-llm-structured-text/SKILL.md

@@ -1,6 +1,7 @@
 ---
 name: regex-vs-llm-structured-text
 description: Decision framework for choosing between regex and LLM when parsing structured text — start with regex, add LLM only for low-confidence edge cases.
+origin: ECC
 ---
 
 # Regex vs LLM for Structured Text Parsing