[FR] Add "save_to_latex" method to EXPLICITELY output to Latex for PPStructureV3 and PaddleOCR-VL

[Heavygrass]

In the PaddleOCR-VL Usage Tutorial there seems to be no way to EXPLICITELY output to Latex for PaddleOCR-VL.

save_to_markdown() may output to HTML if there's no formulas. One has to find a way to convert HTML to Latex then.

I believe simply adding a parameter to save_to_markdown() is not enough, b/c there may be growing number of very specific parameters for saving to Latex.
For example there may be a parameter whether to generate Latex preamble like \usepackage etc.

With save_to_markdown() one needs to determine for each output file whether its HTML or Latex (or possibly some other format?), and rename each file, which takes significant time for many output files.

Thank you.