Abseil LTS 20250512.0

What's New:

The polyfill types absl::any, absl::optional, and absl::variant are now aliases for std::any, std::optional, and std::variant in all builds. (Note that the polyfill implementation absl::string_view remains at the present time, but it defaults to being an alias std::string_view in all builds.)
Added absl::FastTypeId<Type>(), which evaluates at compile-time to a unique id for the passed-in type.
Added absl::endian and absl::byteswap polyfills (https://github.com/abseil/abseil-cpp/commit/25bce1236b030ce8952ec06e5dd1a285f05b400a).

Abseil now requires at least C++17 and follows Google's Foundational C++ Support Policy. See this table for a list of currently supported versions compilers, platforms, and build tools.
Nullability template types are deprecated and will be removed in a future release. The macro-style annotations (absl_nonnull, absl_nullable) should be used instead (https://github.com/abseil/abseil-cpp/commit/caf854d58c061808bae2a41f2b7da21a3ba74028).

Baseline: bc257a88f7c1939f24e0379f14a3589e926c950c