[boost] [release] Boost 1.81.0 beta 1 released

Boost release 1.81.0 beta 1 is now available at: https://boostorg.jfrog.io/artifactory/main/beta/1.81.0.beta1/source/ The SHA256 checksums are: 135f03965b50d05baae45f49e4b7f2f3c545ff956b4500342f8fb328b8207a90 boost_1_81_0_b1.tar.gz 736b041748d04c573d145613161cf2e54beb210c5511b67e6fac5510b82b6646 boost_1_81_0_b1.7z 941c568e7ac79aa448ac28c98a5ec391fd1317170953c487bcf977c6ee6061ce boost_1_81_0_b1.tar.bz2 c58d50acf58a98d4f5a7d891257d154efa50ca90312ca446586c7b4f9b7d3f14 boost_1_81_0_b1.zip Release notes (still need updates): https://www.boost.org/users/history/version_1_81_0.html Please try the beta and report any problems you encounter. Thanks to everyone who contributed to the release. -- Boost Release Team