CLN: Move to a more conventional C/C++ project structure

[mferrera]

Resolves #1128

Only code changes are removing the custom bool type (needed in C89) for the C99 bool type, some shuffling of include files, and things that clang-format picked up and reformatted.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (3c68537) 80.10% compared to head (b98d40c) 80.08%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1131 +/- ## ========================================== - Coverage 80.10% 80.08% -0.02% ========================================== Files 98 98 Lines 13609 13609 Branches 2197 2197 ========================================== - Hits 10901 10899 -2 - Misses 1971 1972 +1 - Partials 737 738 +1 ```

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