Docs/vi posterior notebook

[Shamik-07]

Created a new VI notebook and updated the docs.

Note

The q details have been retrieved from here and the vi_method details from here

Important

With my limited understanding of sampling methods and with research, i have included the "when to use VI over MCMC".

Closes #1765 .

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.86%. Comparing base (3c60a97) to head (47b0632).

Additional details and impacted files

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  Coverage   87.86%   87.86%           
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  Files         140      140           
  Lines       12726    12726           
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  Hits        11182    11182           
  Misses       1544     1544           

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[janfb]

Hi @Shamik-07, apologies for the delay in reviewing this! We've had a high volume of PRs recently.

On a first look, it's a good idea to add a how-to-guide on VI methods. I will add a more concrete review soon.

Thanks for your patience 🙏

[janfb]

Thanks for putting this together, and please excuse that we did not follow through with the detailed review we promised. Since this PR was opened, the VI API and the how-to-guide structure have changed substantially, and the current proposal would require a significant rewrite and revalidation rather than incremental review.

We’re therefore going to close this PR while keeping #1765 open. The proposed outline remains useful, but any renewed work should start from current main, include an executed analytic validation example.