katana-canvas-forge: versioned diagram rendering and document export runtime.
This crate owns Mermaid / Draw.io rendering and HTML / PDF / PNG / JPEG export responsibilities extracted from KatanA. KatanA consumes this crate as a library through the renderer runtime interface defined here.
Status: v0.1.0 transfers the KatanA Mermaid / Draw.io / export runtime into this independent crate.