Fix audit follow-up gates
- remove gray-matter and use local YAML frontmatter handling
- upgrade DOMPurify and clear production advisories
- make CLI/MCP smoke skip cleanly without VK_API_KEY
- reduce initial JS below the Mantine QA budget
Closes#753Closes#754Closes#755
* feat: global system health status bar (#185)
* fix: export system-health types from shared barrel
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Co-authored-by: Brad Groux <bradgroux@users.noreply.github.com>