fix: resolve PHPCS coding standard violations for CI

- Convert all PHP files from CRLF to LF line endings
- Reformat multi-line function calls per WPCS standard
  (opening paren last on line, closing paren on own line)
- Fix assignment-in-conditional in single-peptide.php
- Change double quotes to single quotes in content-none.php
- Exclude InvalidClassFileName sniff (standard WP functions.php pattern)
- Fix archive-peptide.php opening PHP tag placement

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

archive-peptide.php

@@ -70,4 +70,5 @@ get_header();
 	</div>
 </main>
 
-<?php get_footer();
+<?php
+get_footer();