fix: convert raw HTML to markdown and fix deprecated HTML entities
Content fixes:
- speak-to-me: Convert blockquote to markdown, decode entities
- wp_patcher: Convert pre blocks to fenced code, markdown blockquote
- manage-your-passwords: Convert a tags and blockquotes to markdown, add acronym shortcode, decode entities
- playing-with-colors: Convert a tag to markdown
- pure-nerdgasm: Mark as draft (YouTube embed lost in export)
- r-i-p-steve-jobs: Replace figure with image shortcode
- responsibility: Convert blockquote to markdown
