Add configuration files and patches for R, SDL2, SDL3, Tk, and Vala

- Introduced `r.toml` for R package configuration, including build flags and dependencies.
- Added `sdl2-compat.toml` for SDL2 compatibility layer with SDL3, specifying build and runtime dependencies.
- Created a patch for SDL3 to handle cases when XInput2 is not available, ensuring compatibility.
- Added `sdl3.toml` for SDL3 configuration, including build flags and dependencies.
- Introduced `tk.toml` for Tk configuration, detailing build flags and runtime dependencies.
- Added a patch for Vala to ensure POSIX compliance in the test runner script, improving portability.

extra/lua/lua.pc

@@ -0,0 +1,20 @@
+V=%VER%
+R=%REL%
+
+prefix=/usr
+INSTALL_BIN=${prefix}/bin
+INSTALL_INC=${prefix}/include
+INSTALL_LIB=${prefix}/lib
+INSTALL_MAN=${prefix}/man/man1
+INSTALL_LMOD=${prefix}/share/lua/${V}
+INSTALL_CMOD=${prefix}/lib/lua/${V}
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: Lua
+Description: An Extensible Extension Language
+Version: ${R}
+Requires: 
+Libs: -L${libdir} -llua -lm
+Cflags: -I${includedir}