Anticipatory version of C++23 `std::unreachable()` (#3099)
Anticipatory version of C++23 `std::unreachable()` (#3099)

C++23 introduces std::unreachable(). It standardizes compiler intrinsics that have long been present. This PR contains an anticipatory version that supports all the compilers TileDB supports.

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* Anticipatory version of C++23 `std::unreachable()`

* Add more documentation links

* Fix the fix to a typo

* clang-format
TileDB-Inc/TileDB,TileDB-Inc/TileDB,TileDB-Inc/TileDB,TileDB-Inc/TileDB