[compiler] Fix fbt for the ∞th time

We now do a single pass over the HIR, building up two data structures:
* One tracks values that are known macro tags or macro calls.
* One tracks operands of macro-related instructions so that we can later group them.

After building up these data structures, we do a pass over the latter structure. For each macro call instruction, we recursively traverse its operands to ensure they're in the same scope. Thus, something like `fbt('hello' + fbt.param(foo(), "..."))` will correctly merge the fbt call, the `+` binary expression, the `fbt.param()` call, and `foo()` into a single scope.