…r in parse_operator_after_ret_type

If I want to make it more granular I can later.

Lexer tokens now tracked using TokenSlice. ParserContext as the id for current token during traversal.
Last progress on errors needs updates to interface.parsing.cpp
Not adding message support yet as that will need to revamped with the logging, right now just focused on getting both lexer on parser to use proper info data structures.
Thinking of separating ParseContext from the general lib Context, plan is to just have the parser context have its allocator and other references it needs.
So there will seem to be redundant parameter passing to some procedures for now.
The big endgoal of this other than the parser's compression is the ability to support mult-threading.
Immediate concern other than making sure everything necessary is only within ParseContext, etc is things related to logging, or otherwise that is not thread dependent.
Those can get guarded but I don't have full intuition on what will have that (most likely the library's provided allocator/s as well will need guards introduced).
I'll concern myself more with charting those out once things are at least lifted properly. Worst case a trivial situation can be achived by the user by just abusing multiple contextes/allocators/etc as we already have in place.

…ontinuation)

# Conflicts:
#	base/components/code_types.hpp