Emacs org-mode with babel for executing code blocks to generate the diagrams prior to exporting to html/pdf is my flow for this. It still has a steeper learning

Emacs org-mode with babel for executing code blocks to generate the diagrams prior to exporting to html/pdf is my flow for this. It still has a steeper learning curve for non-technical users, but if you use post-commit hooks you can have people just make changes that way and let the scripts do the work.