//utils: Add some scaffolding code

Error is.. well, an error. Unlike std::error_code, or etc, we use a
string so that code can attach its own context. It's not perfect, but
it's better than error categories, and that's good enough.

A early idea for the api of kvm::VM is provided, but I'm not attached to
it.

cmake/ProjectFuncs.cmake

@@ -2,7 +2,7 @@ function(tv2hv_target target)
 	target_compile_definitions(${target} PRIVATE "$<$<CONFIG:DEBUG>:TV2HV_DEBUG>")
 	#target_include_directories(${target} PRIVATE ${PROJECT_SOURCE_DIR})
 	target_compile_features(${target} PRIVATE cxx_std_23)
-	target_include_directories(${target} PRIVATE ${PROJECT_SOURCE_DIR}/src/lib ${CMAKE_CURRENT_BINARY_DIR})
+	target_include_directories(${target} PRIVATE ${PROJECT_SOURCE_DIR}/src ${CMAKE_CURRENT_BINARY_DIR})
 endfunction()
 
 function(_tv2hv_set_alternate_linker)