Add a 'Render diagrams and formulas natively' section to the wiki skill:
prefer native Mermaid for diagrams and KaTeX ($...$) for formulas over ASCII
art / unicode-in-code, as the default (but not for the sake of it). Records the
mechanics learned in practice — Mermaid label/colour discipline and real-render
validation; KaTeX as a LaTeX-math subset, dollar-only delimiters, the table
pipe/percent escapes, and the closing-$-glued-to-slash boundary trap — plus the
two-gate validation discipline (parser gate + Gitea render-parity, table
integrity, adversarial semantic-equivalence), since valid != correct != rendered.
Also a checklist item and a description clause.
Standalone utility skill (manual /wiki, not a pipeline phase). Fixes the house rules for repository-wiki articles: durable project-neutral knowledge only (no implementation state — that belongs in docs/), every load-bearing fact backed by a validated external source, claims marked law/convention/corrected, an overview page plus cross-linked detail pages each with a References section, written in English. Documents the wiki mechanics (own <repo>.wiki.git, slugs, edit paths, special files) and the wiki-vs-docs/ decision rule.
README: list `wiki` among the on-demand utility skills, kept out of the pipeline table.
Brummel