Headers of some essential modules added

src/parser.h

+// parser.h
+#ifndef PARSER_H
+#define PARSER_H
+
+#include "process.h"
+
+int parse_workload(const char *filename, workload_item *items, size_t *count);
+
+#endif

src/process.h

+#ifndef PROCESS_H
+#define PROCESS_H
+
+#include <stddef.h>
+
+typedef struct {
+    int pid;
+    int ppid;
+    size_t ts;
+    size_t tf;
+    size_t idle;
+    char cmd[32]; // assuming max command length
+    int prio;
+} workload_item;
+
+#endif

src/scheduler.h

+// scheduler.h
+#ifndef SCHEDULER_H
+#define SCHEDULER_H
+
+#include "process.h"
+
+void run_scheduler(workload_item *items, size_t count);
+
+#endif
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