fix: add strings terminators

src/vm/fzl_vm.c

@@ -1,11 +1,8 @@
-#include <common/fzl_builtins.h>
 #include <common/fzl_opcodes.h>
 #include <common/fzl_types.h>
 #include <common/fzl_value.h>
 #include <compiler/utils/fzl_const_pool.h>
-#include <stdbool.h>
 #include <stddef.h>
-#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -16,11 +13,10 @@
 #include <vm/internals/opcode.h>
 
 char last_err[256];
+char internal_error[256];
 size_t last_jmp_ip       = 0;
 size_t total_jmp_on_same = 0;
 
-static char *expect_hdr = "FZL\0\2";
-
 fzl_vm_t *fzl_mkvm(fzl_vm_reader_t *reader)
 {
   if (!reader)