Third-party components

libimago - John Tsiombikas, LGPL-3.0-or-later.
Source: source/third_party/imago/
License texts: COPYING and COPYING.LESSER in that directory.
Pinned revision: 99f2bfe30b7441251e2d0bc2d72d1e6edd04ae36.
PNG compatibility changes are applied during CMake configuration by
source/cmake/ImageDependencies.cmake: RGB expansion, short I/O checks and
removal of a duplicate IEND write. The upstream sources remain unchanged;
the patched file and PNG-only module registration are generated in the build.

libpng 1.6.59 - source/third_party/libpng/LICENSE and LICENSES/.
zlib 1.3.2 - source/third_party/zlib/LICENSE.
Microsoft GSL 4.2.2 - MIT, source/third_party/ms_gsl/LICENSE.
Complete sources and original notices for all four libraries are included.

These components retain their original licenses, independently of the
project's MIT license. CMake contains the original download URLs and hashes.
