port 2A step 4: platform skeleton + rest of the 2V3 header closure

- Mirror the remaining non-Python 2V3 closure headers (98 more, 173 total): EffectLib,
  EterGrnLib, SpeedTreeLib, SphereLib, PRTerrainLib, EterImageLib, EterBase/Poly, cipher/tea,
  EterLib Grp*/IME/Input/MSWindow/StateManager, GameLib actor/map/race headers, EterPack.
- SDK shims: granny.h, SpeedTreeRT.h, imm.h, Dimm.h (the SDK MIDL header, not mirrored),
  dinput/d3dx8 additions; D3D8 render-state enums, FVF macros and the COM resource hierarchy;
  more Win32 GDI/handle types with layout static_asserts.
- PORT edits for MSVC-permissive code (typename, friend visibility, <algorithm>, pointer→uintptr_t)
  and PRTerrainLib/StdAfx.h dropping the ScriptLib/Python include.
- port_logic links the vendored cryptopp/minilzo.
- extension/src/platform: port_platform target with 103 generated stub files (1917 function
  stubs, 146 static members) from the new platform_stub.py (clang -ast-dump-filter);
  MT_PLATFORM_STUB() marks every unimplemented body. libmtgodot links port_platform and
  port_gate.sh builds it.

Gate: macOS, Android, iOS, Windows (mingw) PASS; Linux BLOCKED (no toolchain).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

extension/src/platform/EterBase/MappedFile.cpp

@@ -0,0 +1,107 @@
+// Platform skeleton for EterBase/MappedFile.h (40250 EterBase/MappedFile.cpp), generated by platform_stub.py.
+// Every MT_PLATFORM_STUB() body is unimplemented: replace it with the platform implementation.
+#include "EterBase/StdAfx.h"
+#include "EterBase/MappedFile.h"
+
+#include "../PlatformStub.h"
+
+CMappedFile::CMappedFile()
+{
+	MT_PLATFORM_STUB();
+}
+
+CMappedFile::~CMappedFile()
+{
+	MT_PLATFORM_STUB();
+}
+
+auto CMappedFile::Link(DWORD, const void *) -> void
+{
+	MT_PLATFORM_STUB();
+}
+
+auto CMappedFile::Create(const char *) -> BOOL
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<BOOL>();
+}
+
+auto CMappedFile::Create(const char *, const void **, int, int) -> BOOL
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<BOOL>();
+}
+
+auto CMappedFile::Get() -> LPCVOID
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<LPCVOID>();
+}
+
+auto CMappedFile::Destroy() -> void
+{
+	MT_PLATFORM_STUB();
+}
+
+auto CMappedFile::Seek(DWORD, int) -> int
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<int>();
+}
+
+auto CMappedFile::Map(const void **, int, int) -> int
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<int>();
+}
+
+auto CMappedFile::Size() -> DWORD
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<DWORD>();
+}
+
+auto CMappedFile::GetPosition() -> DWORD
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<DWORD>();
+}
+
+auto CMappedFile::Read(void *, int) -> BOOL
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<BOOL>();
+}
+
+auto CMappedFile::GetSeekPosition() -> DWORD
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<DWORD>();
+}
+
+auto CMappedFile::BindLZObject(CLZObject *) -> void
+{
+	MT_PLATFORM_STUB();
+}
+
+auto CMappedFile::BindLZObjectWithBufferedSize(CLZObject *) -> void
+{
+	MT_PLATFORM_STUB();
+}
+
+auto CMappedFile::AppendDataBlock(const void *, DWORD) -> BYTE *
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<BYTE *>();
+}
+
+auto CMappedFile::GetCurrentSeekPoint() -> BYTE *
+{
+	MT_PLATFORM_STUB();
+	return mt_platform_stub_return<BYTE *>();
+}
+
+auto CMappedFile::Unmap(LPCVOID) -> void
+{
+	MT_PLATFORM_STUB();
+}