cmake: misc tidy-ups

cmake: misc tidy-ups

- replace `add_compile_options()`,  `add_definitions()` with directory
  properties. To harmonize this across all scripts. The new commands are
  verbose, but describe better how they work. The syntax is also closer
  to setting target properties, helps grepping.

- prefer `CMAKE_INSTALL_PREFIX` over `--prefix` (in tests, CI).

- tidy up cmake invocations.

- formatting.

Closes #16238