ProgramMemory: no longer offer mutable iterators

[firewave]

This avoids copy-on-write with range loops.

[firewave]

-D__GNUC__ --check-level=exhaustive ../lib/utils.cpp

Clang 17 773,369,412 -> 767,405,289
GCC 14 794,493,015 -> 788,810,953

The example from https://trac.cppcheck.net/ticket/10765#comment:4:

Clang 17 3,988,168,871 -> 3,988,074,912
GCC 14 4,098,327,498 -> 4,098,726,601

[firewave]

Suggesting std::as_const() is tracked via https://trac.cppcheck.net/ticket/11208.

[pfultz2]

Can we just remove the non-const overload for begin and end? I dont think its ever used.

[firewave]

Can we just remove the non-const overload for begin and end? I dont think its ever used.

Actually - yes.