[FEA]: Implement P0843 `std::inplace_vector`

[miscco]

Is this a duplicate?

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Area

libcu++

Is your feature request related to a problem? Please describe.

std::inplace_vector has been merged into the C++26 working draft.

This is an exiting new container that will be quite useful to our users

Describe the solution you'd like

Implement std::inplace_vector and backport it to C++17 so that we can ensure broad usability

Describe alternatives you've considered

No response

Additional context

No response