Inspect special purpose chars using their unicode representation

[sabiwara]

This reduces confusion when working with zero-width characters or alternative spaces.

Relates to #13673

I used this as a base and compared with python which seems to have a similar strategy for almost all of these.

[sabiwara]

I think it's especially good for this one, since we already have something to prevent vulnerabilities around it in the tokenizer:

elixir/lib/elixir/src/elixir_tokenizer.hrl

Lines 22 to 24 in e8ea6a5

	%% Bidirectional control
	%% Retrieved from https://trojansource.codes/trojan-source.pdf
	-define(bidi(C), C =:= 16#202A;