Add example of new to_string method

[mborland]

No description provided.

[cppalliance-bot]

An automated preview of the documentation is available at https://325.int128.prtest3.cppalliance.org/libs/int128/doc/html/index.html

If more commits are pushed to the pull request, the docs will rebuild at the same URL.

2026-02-11 16:07:52 UTC

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.03%. Comparing base (e103fc2) to head (1fb367b).
⚠️ Report is 4 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop     #325   +/-   ##
========================================
  Coverage    99.03%   99.03%           
========================================
  Files           63       64    +1     
  Lines         5369     5403   +34     
  Branches      1661     1686   +25     
========================================
+ Hits          5317     5351   +34     
  Misses          21       21           
  Partials        31       31           

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