build: sync infra to 749c558 for CMake 4.4 and libc++ _FORTIFY_SOURCE

[steve-downey]

Syncs infra/ from 7b66b85 to 749c558, picking up three upstream commits. Both changed files fix real CI breakage.

enable-experimental-import-std.cmake — CMake 4.4.0 gate. The CMAKE_EXPERIMENTAL_CXX_IMPORT_STD UUID changes with each CMake release. After #68 bumped cmake from 4.3.4 to 4.4.0, the VERSION_GREATER_EQUAL "4.3.0" branch no longer matched a supported UUID, so import std builds stopped enabling the feature.

llvm-libc++-toolchain.cmake — _FORTIFY_SOURCE. Now appends -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0 alongside -stdlib=libc++.

Verification

Both vendored files match bemanproject/infra at the pinned hash byte-for-byte — no hand-edited drift:

$ gh api "repos/bemanproject/infra/contents/cmake/enable-experimental-import-std.cmake?ref=749c558..." | diff - infra/cmake/...
MATCHES pinned infra commit

The upstream range touches only those two files, so nothing else needed syncing:

$ gh api repos/bemanproject/infra/compare/7b66b85...749c558 --jq '...'
{"commits":3,"files":[
  {"file":"cmake/enable-experimental-import-std.cmake","status":"modified"},
  {"file":"cmake/llvm-libc++-toolchain.cmake","status":"modified"}]}

Split out from #80 (test coverage) so it can land independently — that PR's CI may well be waiting on this.

🤖 Generated with Claude Code

[steve-downey]

Closing as a duplicate of #77, which I missed before opening this — #77 predates it (2026-08-01) and carries byte-identical changes to all three files. No need for two.