Add requirements checks and fix indirect implementation

[jbcoe]

Add requirements checks for indirect and polymorphic, fix implementations to adhere to the proposed formal wording.

Fix CMake handling of compile checks using object libraries.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.69%. Comparing base (563d12c) to head (08445f8).
Report is 12 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #440      +/-   ##
==========================================
+ Coverage   98.68%   98.69%   +0.01%     
==========================================
  Files           7        7              
  Lines         608      615       +7     
==========================================
+ Hits          600      607       +7     
  Misses          8        8              

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