topdown/every: improve traces (#4351)

The traces we had before were pretty much accidental. Now, we're
emitting traces in a controlled manner.

The pretty-printer mis-aligns the "Redo every" trace, but that's more
involved to fix and left out for this change.

Also some ast-related changes wrapped into this:

* ast/transform: add Every case
* ast/compile_test,topdown/topdown_partial_test: adjust tests
* ast/compile_test: add CheckRecursion test with 'every'

Signed-off-by: Stephan Renatus <stephan.renatus@gmail.com>