cleanup: remove Godot-era test data, formats/, dead proto reader and duplicates

- test/: bgfx/Godot render goldens and compare shots nothing reads any more;
  the Granny oracle result m2-numeric.json moves to oracle/
- formats/: only the .spt sniffer was still linked; it moves into
  platform/SpeedTreeLib, the rest and tools/map_probe go
- bgm/ duplicated Client/BGM byte for byte; tools/root archived root scripts
  that root.epk already holds; extension/src/proto had no build reference
- GEMINI.md duplicated AGENTS.md

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/CMakeLists.txt

@@ -13,9 +13,6 @@ target_link_libraries(oracle_diff PRIVATE xrender::libgr2)
 add_executable(anim_probe anim_probe/main.cpp)
 target_link_libraries(anim_probe PRIVATE xrender::libgr2)
 
-# SHINSOO W0：一张地图的 load report（setting / textureset / 区块二进制 / areadata）
-add_executable(map_probe map_probe/main.cpp)
-target_link_libraries(map_probe PRIVATE xrender::formats)
 
 # gr2dump --gltf 需要 tinygltf（M0 T8 辅助、可延后）：
 #   if(TARGET tinygltf) target_link_libraries(gr2dump PRIVATE tinygltf) endif()