Enhance mdexport to annotate rand() and randn() using sympy

[Utkarsha2811]

Problem: The Markdown exporter currently displays raw strings for initializations using rand() and randn() without providing mathematical context.

Solution: I used SymPy to analyze these expressions. The exporter now calculates and displays exact lower/upper bounds for rand() and the mean/variance for randn() in the exported Markdown descriptions.

[mstimberg]

Hi @Utkarsha2811. Thanks for the PR! I won't be able to review it right away, so please be a bit patient.

[Utkarsha2811]

Hi @Utkarsha2811. Thanks for the PR! I won't be able to review it right away, so please be a bit patient.

Thanks, Meanwhile I'll recheck and update PR description.

[mstimberg]

Hi @Utkarsha2811, sorry for the delay in getting back to this PR. Since you opened it, the master branch has moved on, and it now triggers the test suite for pull requests. Could you please merge the current master into your branch so that the test suite runs here as well? Thanks 🙏

[Utkarsha2811]

Hey @mstimberg, I've merged master so the test suite will run. I also took the opportunity to do some minor refactoring and added tests while I was at it. Let me know what you think!