[wpilib] Document simulation APIs (#3079)

- Remove sim checkstyle suppression
- Add [[nodiscard]] to C++ register callback functions
- Add a couple of missing sim functions

Co-authored-by: Peter Johnson <johnson.peter@gmail.com>
Co-authored-by: Starlight220 <yotamshlomi@gmail.com>

wpilibc/src/main/native/include/frc/simulation/SimHooks.h

@@ -11,6 +11,11 @@
 
 namespace frc::sim {
 
+/**
+ * Override the HAL runtime type (simulated/real).
+ *
+ * @param type runtime type
+ */
 void SetRuntimeType(HAL_RuntimeType type);
 
 void WaitForProgramStart();
@@ -19,16 +24,40 @@ void SetProgramStarted();
 
 bool GetProgramStarted();
 
+/**
+ * Restart the simulator time.
+ */
 void RestartTiming();
 
+/**
+ * Pause the simulator time.
+ */
 void PauseTiming();
 
+/**
+ * Resume the simulator time.
+ */
 void ResumeTiming();
 
+/**
+ * Check if the simulator time is paused.
+ *
+ * @return true if paused
+ */
 bool IsTimingPaused();
 
+/**
+ * Advance the simulator time and wait for all notifiers to run.
+ *
+ * @param deltaSeconds the amount to advance (in seconds)
+ */
 void StepTiming(units::second_t delta);
 
+/**
+ * Advance the simulator time and return immediately.
+ *
+ * @param deltaSeconds the amount to advance (in seconds)
+ */
 void StepTimingAsync(units::second_t delta);
 
 }  // namespace frc::sim