docs(checks): add guidelines for headers and verifying

[Nytelife26]

Relevant issues

Resolves #1408. May impact #1437.

Brief

This adds the final documentation required to comprehensively evaluate all current and future checks.

A rendered preview is available.

Changes

• Add a "Verification" section to the checks documentation

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.62%. Comparing base (1f4c0eb) to head (45ce0f3).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1479   +/-   ##
=======================================
  Coverage   92.62%   92.62%           
=======================================
  Files         100      100           
  Lines        1017     1017           
=======================================
  Hits          942      942           
  Misses         75       75           

Flag	Coverage Δ
macos-latest	92.03% <ø> (ø)
py3.10	92.62% <ø> (ø)
py3.11	92.62% <ø> (ø)
py3.12	92.62% <ø> (ø)
py3.13	92.03% <ø> (ø)
py3.14	92.03% <ø> (ø)
ubuntu-latest	92.03% <ø> (ø)
windows-latest	92.62% <ø> (ø)

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