Refactor

Move json_value and obj_t to same file
 - Rename json_obj.* -> json_value.*
 - Move `print_json_value(...)` to json_value.*

Move `err_ctx(...)` to util.*

parse.h now only exposes `parse_json_value(...)`

include/parse.h

@@ -2,31 +2,10 @@
 #ifndef _PARSE_H
 #define _PARSE_H
 
-#include "json_obj.h"
-#include <stdbool.h>
-#include <stdint.h>
-#include <stdio.h>
+#include "json_value.h"
 
-enum json_type { object,
-    array,
-    string,
-    number,
-    boolean,
-    null };
-
-struct json_value {
-    enum json_type type;
-    union {
-        obj_t* object;
-        struct json_value** array;
-        char* string;
-        bool boolean;
-        double number;
-    };
-};
+#include <stdio.h> // FILE*
 
 struct json_value parse_json_value(FILE* fp);
 
-void print_json(struct json_value val, int indent);
-
 #endif