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>

formats/terrain_files.h

@@ -1,44 +0,0 @@
-// 区块二进制：height.raw / tile.raw / attr.atr / water.wtr。
-// 真值来源：PRTerrainLib/Terrain.cpp（LoadHeightMap / RAW_LoadTileMap / LoadAttrMap /
-// LoadWaterMapFile）+ Terrain.h / TerrainType.h 常量。SHINSOO §5.3。
-//
-//   XSIZE = 128
-//   height.raw : 无头，u16 LE [131*131]              (HEIGHTMAP_RAW = XSIZE+3)
-//   tile.raw   : 无头，u8    [258*258]               (TILEMAP_RAW   = XSIZE*2+2)
-//   attr.atr   : 6B 头 {u16 magic=2634, u16 w=256, u16 h=256} + u8 [256*256]
-//   water.wtr  : 7B 头 {u16 magic=5426, u16 w=128, u16 h=128, u8 layers}
-//                + u8 [128*128] + layers×(u16 或 u32) 层高
-#pragma once
-#include <cstdint>
-#include <string>
-#include <vector>
-
-namespace fmt {
-
-constexpr int HEIGHTMAP_RAW_XY = 131; // 128+3
-constexpr int TILEMAP_RAW_XY   = 258; // 128*2+2
-constexpr int ATTRMAP_XY       = 256; // 128*2
-constexpr int WATERMAP_XY      = 128;
-constexpr uint16_t ATTR_MAGIC  = 2634;
-constexpr uint16_t WATER_MAGIC = 5426;
-
-struct HeightMap {
-    std::vector<uint16_t> raw; // 131*131, 行主序（含 1 圈边界样本）
-    uint16_t at(int sx, int sy) const { // 与 Terrain.h GetHeight 一致：+1 偏移
-        return raw[(sy + 1) * HEIGHTMAP_RAW_XY + (sx + 1)];
-    }
-};
-struct TileMap  { std::vector<uint8_t> raw; }; // 258*258
-struct AttrMap  { std::vector<uint8_t> data; }; // 256*256（去头）
-struct WaterMap {
-    uint8_t layer_count = 0;
-    std::vector<uint8_t> ids;      // 128*128；0xFF = 无水
-    std::vector<int32_t> heights;  // layer_count 个
-};
-
-bool load_height_map(const std::string& path, HeightMap& out, std::string* err);
-bool load_tile_map(const std::string& path, TileMap& out, std::string* err);
-bool load_attr_map(const std::string& path, AttrMap& out, std::string* err);
-bool load_water_map(const std::string& path, WaterMap& out, std::string* err);
-
-} // namespace fmt