Document SVG requirements so users know how to do it

[ronaldtse]

When saving a vector image in Illustrator, you need to export it using "Export as..." > "SVG".

The normal "Save as..." > "SVG" will create an SVG that crashes Apache Batik.

Export options:

We need to update metanorma.org to explain what Metanorma's SVG requirements. SVG has never been a clean format and we need detailed steps to tell people how to export proper SVGs.

Originally posted by @ronaldtse in https://github.com/metanorma/mn-samples-jis/issues/21#issuecomment-2032469287

[ronaldtse]

@anermina @manuelfuenmayor you might have additional insights too! Please post them here.

[ronaldtse]

Also PNG DPIs are important, @Intelligent2013 can you give some insights into what DPIs work with raster images here?

[Intelligent2013]

Metanorma PDF generation mechanism (mn2pdf tool based on the Apache FOP) uses the DPI from the raster image meta-information. If image doesn't have the DPI value, then the 96dpi is using for the image rendering. If image doesn't fit on the page, then it will be scaled down automatically to fit on the page. For images in the table, to properly rendering them, highly recommend to set the DPI for the images or set the width/height attribute in the adoc.