[hal, wpilib] Add OpMode support (#7744)

User code:
- OpModeRobot used as the robot base class
- LinearOpMode and PeriodicOpMode are provided opmode base classes
- In Java, annotations can be used to automatically register opmode classes

Additional user code functionality:
- OpMode (string) is available in addition to the overall
auto/teleop/test robot mode
- OpMode does not indicate enable (enable/disable is still separate)
- The HAL API uses integer UIDs; these are exposed at the user API level
as well for faster checks
- User code creates opmodes on startup (these have name, category,
description, etc).

DS:
- DS will present opmode selection lists for auto and teleop for
match/practice. During a match, the DS will automatically activate the
selected opmode in the corresponding match period.
- For testing, an overall mode is selected (e.g. teleop/auto/test) and a
single opmode is selected

Future work:
- Command framework support/integration
- Python annotation support
- Unit tests (needs race-free DS sim updates)
- Porting of examples

Co-authored-by: Joseph Eng <91924258+KangarooKoala@users.noreply.github.com>

wpilibc/src/main/native/cpp/internal/DriverStationModeThread.cpp

@@ -10,55 +10,30 @@
 
 using namespace wpi::internal;
 
-DriverStationModeThread::DriverStationModeThread() {
+DriverStationModeThread::DriverStationModeThread(wpi::hal::ControlWord word)
+    : m_userControlWord{word.GetValue().value} {
+  HAL_ProvideNewDataEventHandle(m_event.GetHandle());
   m_keepAlive = true;
-  m_thread = std::thread{[&] { Run(); }};
+  m_thread = std::thread{[this] { Run(); }};
 }
 
 DriverStationModeThread::~DriverStationModeThread() {
+  HAL_RemoveNewDataEventHandle(m_event.GetHandle());
   m_keepAlive = false;
+  m_event.Set();
   if (m_thread.joinable()) {
     m_thread.join();
   }
 }
 
-void DriverStationModeThread::InDisabled(bool entering) {
-  m_userInDisabled = entering;
-}
-
-void DriverStationModeThread::InAutonomous(bool entering) {
-  m_userInAutonomous = entering;
-}
-
-void DriverStationModeThread::InTeleop(bool entering) {
-  m_userInTeleop = entering;
-}
-
-void DriverStationModeThread::InTest(bool entering) {
-  m_userInTest = entering;
-}
-
 void DriverStationModeThread::Run() {
-  wpi::util::Event event{false, false};
-  HAL_ProvideNewDataEventHandle(event.GetHandle());
-
-  while (m_keepAlive.load()) {
+  for (;;) {
     bool timedOut = false;
-    wpi::util::WaitForObject(event.GetHandle(), 0.1, &timedOut);
+    wpi::util::WaitForObject(m_event.GetHandle(), 0.1, &timedOut);
+    if (!m_keepAlive) {
+      break;
+    }
     wpi::DriverStation::RefreshData();
-    if (m_userInDisabled) {
-      HAL_ObserveUserProgramDisabled();
-    }
-    if (m_userInAutonomous) {
-      HAL_ObserveUserProgramAutonomous();
-    }
-    if (m_userInTeleop) {
-      HAL_ObserveUserProgramTeleop();
-    }
-    if (m_userInTest) {
-      HAL_ObserveUserProgramTest();
-    }
+    HAL_ObserveUserProgram({.value = m_userControlWord});
   }
-
-  HAL_RemoveNewDataEventHandle(event.GetHandle());
 }