Disable MD031 and MD025 linting rules

- MD031: Disable 'blanks around fences' rule to support Hugo choosable shortcodes
- MD025: Disable 'multiple top level headings' rule for guideline files like CLAUDE.md

These rules were incorrectly flagging valid Hugo shortcode syntax used throughout
the docs. Hugo's {{% choosable %}} shortcodes are not actual fenced code blocks
and should not have blank lines around them.

Author: asafashirov

scripts/lint/lint-markdown.js

@@ -299,6 +299,10 @@ const opts = {
         MD034: false,
         // Allow bold/italicized paragraphs
         MD036: false,
+        // Allow code blocks without blank lines around them (Hugo shortcodes like choosable)
+        MD031: false,
+        // Allow multiple top level headings (for CLAUDE.md guideline files)
+        MD025: false,
     },
     customRules: [
         {