Deprecate "bean-report_ledger" ad "bean-report_hledger" toolchains

[trevorld]

• bean-report was removed from beancount in 2020 so deprecate the toolchains that use it. Use the "beancount" toolchain that uses bean-query instead.
• Set up air settings and reformat code files
• Rename filenames to end in .R
• Update CI actions
• Reformat cran-comments.rst to cran-comments.md
• Update to {testthat} v3 and split up tests to match test file to R directory file correspondence

[codecov-commenter]

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Codecov Report

❌ Patch coverage is 87.58389% with 37 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.58%. Comparing base (caebc24) to head (ef69907).
⚠️ Report is 14 commits behind head on master.

Files with missing lines	Patch %	Lines
R/register.R	87.82%	28 Missing ⚠️
R/zzz.R	0.00%	9 Missing ⚠️
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❗ There is a different number of reports uploaded between BASE (caebc24) and HEAD (ef69907). Click for more details.

HEAD has 9 uploads less than BASE

Flag	BASE (caebc24)	HEAD (ef69907)
	10	1

Additional details and impacted files

@@             Coverage Diff             @@
##           master      #29       +/-   ##
===========================================
- Coverage   98.59%   87.58%   -11.02%     
===========================================
  Files           4        5        +1     
  Lines         214      298       +84     
===========================================
+ Hits          211      261       +50     
- Misses          3       37       +34     

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