docs: Add reference of I18n.date and I18n.number

[orangain]

This PR adds missing documentations of I18n.date and I18n.number.

[vercel]

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[codecov]

Codecov Report

Merging #1103 (2d6d881) into main (ea00f55) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1103   +/-   ##
=======================================
  Coverage   82.28%   82.28%           
=======================================
  Files          56       56           
  Lines        1677     1677           
  Branches      458      458           
=======================================
  Hits         1380     1380           
  Misses        173      173           
  Partials      124      124           

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