Add Lua 5.4 scripting integration for dynamic game loading

- Integrated Lua 5.4 engine (32-bit mode for embedded ARM)
- Created LuaGame wrapper class implementing Game interface
- Added C++ bindings exposing renderer, game state, and input to Lua
- Implemented SD card loader for automatic .lua game discovery
- Updated GameLauncher to support std::function for lambda captures
- Made Game class members public for Lua bindings access
- Added example Lua games: counter, snake, bouncing ball
- Included comprehensive API documentation

Games can now be written as .lua text files on SD card and loaded
without recompilation. Build size: 747KB UF2, Lua VM uses ~50-80KB RAM.

lib/lua/lundump.h

@@ -0,0 +1,35 @@
+/*
+** $Id: lundump.h $
+** load precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lundump_h
+#define lundump_h
+
+#include "llimits.h"
+#include "lobject.h"
+#include "lzio.h"
+
+
+/* data to catch conversion errors */
+#define LUAC_DATA	"\x19\x93\r\n\x1a\n"
+
+#define LUAC_INT	0x5678
+#define LUAC_NUM	cast_num(370.5)
+
+/*
+** Encode major-minor version in one byte, one nibble for each
+*/
+#define LUAC_VERSION  (((LUA_VERSION_NUM / 100) * 16) + LUA_VERSION_NUM % 100)
+
+#define LUAC_FORMAT	0	/* this is the official format */
+
+/* load one chunk; from lundump.c */
+LUAI_FUNC LClosure* luaU_undump (lua_State* L, ZIO* Z, const char* name);
+
+/* dump one chunk; from ldump.c */
+LUAI_FUNC int luaU_dump (lua_State* L, const Proto* f, lua_Writer w,
+                         void* data, int strip);
+
+#endif