MSVC translates C enums as signed int, while GCC/Clang uses unsigned
int. The freetype Zig bindings hardcode c_uint for enum backing types,
causing type mismatches when compiling with MSVC target.
Fix by adding @intCast at call sites where enum values are passed to
C functions, and @bitCast for the glyph format tag extraction where
bit-shift operations require unsigned integers.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>