This task follows on from D80, where the CMake infrastructure was introduced to simplify running clang-tidy static analysis checks during the build.
The aim of this task is to:

• Compile a list of all checks that we want to use, from the extensive list of those available, and to decide in what order to introduce them (and to make the corresponding fixes throughout the codebase).
• Work through the ordered list of checks, introducing each check and making the corresponding fixes to the code.
• Once the existing code is passing all checks, an automated check should be introduced in the CI so that any new/modified code is checked.

Sub-tasks will be created for each of these points.