[libc++][spaceship] Implements X::iterator container requirements. (#99343)

This implements the requirements for the container iterator requirements
for array, deque, vector, and `vector<bool>`.

[libc++][spaceship] Implements X::iterator container requirements. (#99343)

This implements the requirements for the container iterator requirements
for array, deque, vector, and `vector<bool>`.

Implements:
- LWG3352 strong_equality isn't a thing

Implements parts of:
- P1614R2 The Mothership has Landed

Fixes: https://github.com/llvm/llvm-project/issues/62486

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