docs: add masker package to CLAUDE.md architecture

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Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: koki-develop

CLAUDE.md

@@ -62,6 +62,9 @@ goreleaser release --snapshot --clean
 - **internal/prettier/**: Code prettifiers
   - Language-specific formatting (CSS, Go, HTML, JSON, XML, YAML)
 
+- **internal/masker/**: Sensitive information masking
+  - Masks API keys, tokens, and other secrets in output
+
 - **internal/styles/**: Theme definitions
   - Custom syntax highlighting themes