wip: working on extern in VM

- Feat: add usage of vm reader instead of old way in vm.c
- Ref: update debug opcodes printing

include/vm/fzl_vm.h

@@ -1,26 +1,16 @@
 #ifndef FZL_VM_H
 #define FZL_VM_H
 
-#include <common/fzl_value.h>
-#include <compiler/utils/fzl_const_pool.h> // NOTE: move outside compiler scope to common
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <vm/fzl_vm_env.h>
-#include <vm/fzl_vm_extern.h>
-#include <vm/fzl_vm_object.h>
+#include <vm/fzl_vm_reader.h>
 
 // VM descriptor
 typedef struct
 {
-  fzl_const_t *consts;
-  size_t consts_count;
-
-  fzl_vm_extern_t *externs;
-  size_t externs_count;
-
-  uint64_t *ops;
-  size_t ops_count;
+  fzl_vm_reader_t *reader;
 
   size_t ip;
 
@@ -41,7 +31,7 @@ typedef struct
 } fzl_vm_t;
 
 // Allocate FZL VM
-fzl_vm_t *fzl_mkvm(const char *filepath);
+fzl_vm_t *fzl_mkvm(fzl_vm_reader_t *reader);
 
 // Load and run code
 int fzl_vm_run(fzl_vm_t *vm);