This adds support for larger buffers > 2 GiB by adding a 64-bit offsets for vectors and strings. This is only for C++ at the moment.

See the 64-bit tests for usage and examples.

What's Changed

• FlatBuffers 64 for C++ by @dbaileychess in #7935
• FlatBuffers Version 23.5.9 by @dbaileychess in #7945

Full Changelog: v23.5.8...v23.5.9