feat(libc): add freestanding types and string helpers

include/string.h

@@ -0,0 +1,14 @@
+#ifndef FROSTBYTE_STRING_H
+#define FROSTBYTE_STRING_H
+
+#include "types.h"
+
+void* memset(void* dest, int value, usize count);
+void* memcpy(void* dest, const void* src, usize count);
+void* memmove(void* dest, const void* src, usize count);
+int memcmp(const void* a, const void* b, usize count);
+usize strlen(const char* str);
+int strcmp(const char* a, const char* b);
+int strncmp(const char* a, const char* b, usize count);
+
+#endif

include/types.h

@@ -0,0 +1,21 @@
+#ifndef FROSTBYTE_TYPES_H
+#define FROSTBYTE_TYPES_H
+
+typedef unsigned char uint8;
+typedef signed char int8;
+typedef unsigned short uint16;
+typedef signed short int16;
+typedef unsigned int uint32;
+typedef signed int int32;
+typedef unsigned long uint64;
+typedef signed long int64;
+
+typedef unsigned long usize;
+typedef signed long isize;
+typedef unsigned long uintptr;
+
+typedef enum { false = 0, true = 1 } bool;
+
+#define nullptr ((void*)0)
+
+#endif