Build position-independent objects (-fPIC)

Set CMAKE_POSITION_INDEPENDENT_CODE so the static library's objects are PIC and stay linkable into a shared object; the host executables build as PIE. The mingw-cross guest is unaffected - position-independence is a no-op for Windows PE targets.

CMakeLists.txt

@@ -4,6 +4,7 @@ project(vmi-engine C)
 set(CMAKE_C_STANDARD 17)               # generation B uses no C23 feature
 set(CMAKE_C_STANDARD_REQUIRED ON)
 set(CMAKE_C_EXTENSIONS ON)             # deliberate: strnlen (POSIX) + void* arithmetic (GNU)
+set(CMAKE_POSITION_INDEPENDENT_CODE ON) # -fPIC on all objects: static lib stays linkable into a shared object
 
 option(VMIE_LTO "Enable LTO" OFF)      # build-only; shipped default is -O2, no LTO