Add missing changelog entries to content/pages/changelog-page.md:
v1.34.0 (2025-12-26): Blog page featured layout with hero post
- blogFeatured frontmatter field for posts
- Hero card displays first featured post with landscape image
- 2-column featured row for remaining featured posts
- 3-column grid for regular posts
v1.35.0 (2025-12-26): Image support at top of posts and pages
- showImageAtTop frontmatter field
- Full-width image display above post header
- Works for both posts and pages
v1.36.0 (2025-12-27): Social footer component
- Customizable social links (8 platform types)
- Copyright with auto-updating year
- showSocialFooter frontmatter field for per-page control
- Configurable via siteConfig.socialFooter
v1.37.0 (2025-12-27): Newsletter Admin UI
- Three-column admin interface at /newsletter-admin
- Subscriber management with search and filters
- Send newsletter panel (post selection or custom email)
- Weekly digest automation (Sunday 9am UTC)
- Developer notifications (subscriber alerts, weekly stats)
- Markdown-to-HTML conversion for custom emails
