Fix integer vector mul/div operators and bindings.

[reduz]

• Remove unnecesary overloads.
• Vector2i and Vector3i mul/div by a float results in Vector2 and Vector3 respectively.
• Create specializations to allow proper bindings.

This fixes #44408 and supersedes #44441 and keeps the same rule of int float returnig float, like with scalars.
WARNING: This most likely breaks GDScript *= operator for typed variables of V2i and V3i. @vnen should give it a check.

[akien-mga]

The documentation for the operators should be updated too as it documented the bugged behaviour.

[akien-mga]

@reduz You also need to update the code examples.