v4.6.0

What's Changed

• Bug fix: Fixed undefined behavior — delete → delete[] for array allocation in qkz80_mem.cc
• Comment corrections: Fixed typos ("partity" → "parity"), misleading comments (8080 vs Z80 default mode, stale function descriptions)
• Include guard cleanup: Renamed stale I8080_* include guards to QKZ80_* to match the library name
• Version sync: Aligned CMakeLists.txt and qkz80.pc.in versions to 4.6.0