Add BVBRC statistics R Markdown document

[AbhirupaGhosh]

Description

What kind of change(s) are included?

• Feature (adds or updates new capabilities)
• Bug fix (fixes an issue).
• Enhancement (adds functionality).
• Breaking change (these changes would cause existing functionality to not work as expected).

Checklist

Please ensure that all boxes are checked before indicating that this pull request is ready for review.

• I have read and followed the CONTRIBUTING.md guidelines.
• I have searched for existing content to ensure this is not a duplicate.
• I have performed a self-review of these additions (including spelling, grammar, and related).
• I have added comments to my code to help provide understanding.
• I have added a test which covers the code changes found within this PR.
• I have deleted all non-relevant text in this pull request template.
• Reviewer assignment: Tag a relevant team member to review and approve the changes.

[jananiravi]

needs the following to serve as a vignette

• to reside in vignettes/
• call specific tidyverse packages (bioc requirement)
• check path for bvbrc_data.tsv & bvbrc vs. bvbrc_clean
• use of named r chunks
• text description between chunks
• missing YAML
• documentation
  cc: @AbhirupaGhosh @eboyer221

[jananiravi]

needs annotation (text around code chunks)

[eboyer221]

Suggested code changes to format the vignette shown in review.
Additional comment : The Rmd should live at vignettes/BVBRC_stats.Rmd rather than doc/ (R packages auto-generated doc/ from vignettes/ at build time).

[eboyer221]

I just pushed a small follow-up that handles a few of the earlier asks: moved the Rmd from doc/ to vignettes/, added a ## heading + short paragraph before each chunk explaining what it computes, and fixed the output chunks at the bottom that had six-backtick fences (they wouldn't have knit correctly as-is). I am approving based on my review - but you may want to double-check the short paragraphs I added before each chunk @AbhirupaGhosh @jananiravi to make sure they look accurate.

[AbhirupaGhosh]

The blocks are helpful. Thanks.
@eboyer221, please merge this if there is no other issue.