PNG encoder: replace literals-only fixed Huffman with stb-style LZ77
matching. Hash-table chain depth scales with compression level (1-9),
giving a smooth tradeoff from fast/light to slow/best. Lazy matching
cancels a match if the next position finds a longer one. Falls back
to store blocks if compressed output is larger than raw.
Screenshot: move hook install from loadScriptFunctionsDetour to
engineInitDetour (GameEngine_MainInitialize at 0x46a400) so it fires
after all DLL_PROCESS_ATTACH hooks. Restore original CTgaFile::Write
prologue before hooking to avoid chaining through UnitXP. Capture
compression level at enqueue time so each queued shot reflects the
quality setting at the moment it was taken. Counter uses hex suffix
(0-F, max 16/sec) and resets each second.