feat(sched): add HBlank and VBlank events to the scheduler

src/emu.zig

@@ -4,14 +4,14 @@ const Bus = @import("bus.zig").Bus;
 
 const cycles_per_frame: u64 = 100; // TODO: How many cycles actually?
 
-pub fn runFrame(sch: *Scheduler, cpu: *Arm7tdmi, bus: *Bus) void {
+pub fn runFrame(sched: *Scheduler, cpu: *Arm7tdmi, bus: *Bus) void {
     var cycles: u64 = 0;
     while (cycles < cycles_per_frame) : (cycles += 1) {
-        sch.tick += 1;
+        sched.tick += 1;
         _ = cpu.step();
 
-        while (sch.tick >= sch.nextTimestamp()) {
-            sch.handleEvent(cpu, bus);
+        while (sched.tick >= sched.nextTimestamp()) {
+            sched.handleEvent(cpu, bus);
         }
     }
 }