v1.8.0

• Feature: default_theme = "dark" | "light" config option to set the initial preview theme. The in-browser sun/moon toggle still works after page load. Closes #19. (#16, thanks @gogongxt)
• Feature: mermaid_elk = true enables the ELK layout engine for mermaid diagrams, producing cleaner layouts for medium and large flowcharts and class diagrams. Off by default (adds ~800 KB CDN fetch). Enable per-diagram with %%{init: {"layout": "elk"}}%%. (#22, thanks @fuzzybear3)
• Security: Token auth on content.md and the live-reload control endpoints. A 128-bit token is generated at server start, threaded through the auto-opened browser URL, and stashed in sessionStorage. No user-facing config needed. (#23)
• Requires: live-server.nvim v1.4.0+ for the token auth feature. If you pin versions, upgrade both together. Lazy.nvim users on branch = "main" or version = "*" are fine.