Add Priority Scheduling with Aging

Implement a priority-based scheduler with aging to prevent starvation.

Requirements:

• Extend Process structure with priority field (0-255, 0 = highest)
• Implement scheduler that selects highest priority READY process
• Add aging mechanism: increase priority of waiting processes every N time units
• Reset priority to static priority when process runs
• Demonstrate priority inversion and how aging prevents starvation
• Show that high priority processes preempt low priority ones
• Ensure all processes eventually run (no starvation)

Test scenarios:

• High priority process starves low priority process
• Aging allows low priority process to eventually run
• Priority inversion scenario with solution