Math: implement m:phant phantom converter (community)

[caio-pizzol]

What

Implement the m:phant (phantom) OMML → MathML converter. Creates invisible spacing placeholders.

OMML: m:phant → m:phantPr (show, zeroWid, zeroAsc, zeroDesc, transp) + m:e
MathML: `` (invisible but takes space)
Spec: §22.1.2.81
Difficulty: Easy

How to implement

1. Create converters/phantom.ts
2. Wrap m:e content in <mphantom>
3. Register as 'm:phant': convertPhantom

Test Document

Download the test file and upload it to the SuperDoc dev app to verify your implementation renders correctly:

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Want to work on this? Check the Contributing Guide to get started. Comment on this issue to let us know you're picking it up.

Ref: SD-2386

[linear]

IT-833