feat: add MLFQ scheduling algorithm and thread scheduler

- Implemented MLFQ (Multilevel Feedback Queue) algorithm with dynamic priority levels and quantum management.
- Created unit tests for MLFQ algorithm covering initialization, demotion, selection, priority boost, preemption, and quantum expiration.
- Developed a ThreadScheduler class supporting FCFS, RR, and PRIORITY scheduling policies for intra-process thread management.
- Added unit tests for ThreadScheduler to validate thread selection and quantum expiration logic.

src/components/ControlBar/ControlBar.tsx

@@ -66,7 +66,7 @@ const ControlBar = () => {
 
   return (
     <div
-      className="h-16 flex items-center px-5 gap-3 bg-slate-800 border-b border-slate-700 shadow-sm"
+      className="h-16 py-2 flex items-center px-5 gap-3 bg-slate-800 border-b border-slate-700 shadow-sm"
       role="toolbar"
       aria-label="Simulation controls"
     >