docs: update related packages sections

[stdlib-bot]

This PR

• updates the related packages section of READMEs to include links to related packages.

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/cceil	$\color{green}165/165$ $color{green}+100.00%$	$\color{green}5/5$ $color{green}+100.00%$	$\color{green}2/2$ $color{green}+100.00%$	$\color{green}165/165$ $color{green}+100.00%$
math/base/special/cround	$\color{green}219/219$ $color{green}+100.00%$	$\color{green}5/5$ $color{green}+100.00%$	$\color{green}2/2$ $color{green}+100.00%$	$\color{green}219/219$ $color{green}+100.00%$

The above coverage report was generated for the changes in this PR.