maint: Apply the MIT-0 license to .appveyor.yml
ci: Migrate the GitHub Actions Windows ARM64 job to Visual Studio 2026
doc: Describe the zstream states that `png_read_end` must handle
fix: Clear stale zstream pointers when releasing the inflate stream
Release libpng version 1.6.59
maint: Rerun `./autogen.sh --maintainer`
maint: Apply the MIT-0 license to .appveyor.yml
ci: Migrate the GitHub Actions Windows ARM64 job to Visual Studio 2026