Move testing around

• Drop Renovate pre-commit hook

  This takes entirely too long to install (I think it downloads all the dependencies for renovate?) just for a hook to validate some config (this was not a fun experience trying to develop on shitty train Wifi...)

• Improve debugging of example tests

  Print more context so the diff is more helpful than:

    -Count: 1
    +Count: 0

  I.e. so I know around which line the change was

• Drop comments unit tests

  Add some more main examples so all these behaviours are covered there.

• Allow skipping individual lines

  The motivation here is per the added docs: final 'return' statements in functions that might be difficult to test.

• Drop profile unit tests

  Like the comments commit: move the testing up to main. This revealed a line I don't think we ever expect to reach in practice.