LibC: Rewrite all the headers.

We now have more or less posix issue 2018 conforming libc headers.

This was a really time consuming and boring operation but it had to
be done.

Now we get to actually start implementing libc :)

libc/CMakeLists.txt

@@ -3,6 +3,7 @@ cmake_minimum_required(VERSION 3.26)
 project(libc CXX ASM)
 
 set(LIBC_SOURCES
+	assert.cpp
 	ctype.cpp
 	fcntl.cpp
 	printf_impl.cpp