feat: Add restart button functionality and motion calibration

- Implemented a restart button with debounce handling and long-press detection in App.cpp.
- Added motion calibration settings to Settings.cpp and Settings.h, allowing for roll and pitch zero offsets.
- Enhanced WebUI to include motion calibration controls and a restart option.
- Updated FaceRenderer to adjust eye and mouth positions based on screen dimensions.
- Introduced deadzone handling for motion sensor readings to improve stability.

src/app/App.cpp

@@ -42,6 +42,12 @@ static unsigned long nextTimeCheckMs = 0;
 static bool lastScheduleSleep = false;
 static String lastConfiguredTz;
 static unsigned long motionWakeUntilMs = 0;
+static bool restartButtonEnabled = true;
+static bool restartButtonLastRaw = true;
+static bool restartButtonStable = true;
+static unsigned long restartButtonLastEdgeMs = 0;
+static unsigned long restartButtonPressedSinceMs = 0;
+static bool restartButtonArmed = true;
 
 static constexpr float DIM_LUX_MIN = 0.0f;
 static constexpr float DIM_LUX_MAX = 300.0f;
@@ -49,6 +55,9 @@ static constexpr uint8_t DIM_CONTRAST_MIN = 0x10;
 static constexpr uint8_t DIM_CONTRAST_MAX = 0xFF;
 static constexpr int ROUTINE_WINDOW_MIN = 5;
 static constexpr unsigned long MOTION_WAKE_MS = 30000UL;
+static constexpr int PIN_RESTART_BUTTON = 2;           // Active-low button to GND
+static constexpr unsigned long BUTTON_DEBOUNCE_MS = 30UL;
+static constexpr unsigned long BUTTON_HOLD_RESTART_MS = 1200UL;
 
 static PlantEventType moodToEvent(FaceRenderer::Mood m) {
   if (m == FaceRenderer::DRY) return EVT_DRY;
@@ -72,6 +81,56 @@ static uint8_t luxToContrast(float lux) {
   return (uint8_t)value;
 }
 
+static void initRestartButton() {
+  pinMode(PIN_RESTART_BUTTON, INPUT_PULLUP);
+  bool raw = digitalRead(PIN_RESTART_BUTTON);
+  restartButtonLastRaw = raw;
+  restartButtonStable = raw;
+  restartButtonLastEdgeMs = millis();
+  restartButtonPressedSinceMs = 0;
+  restartButtonArmed = true;
+
+  Serial.print("[Button] Restart button on GPIO ");
+  Serial.print(PIN_RESTART_BUTTON);
+  Serial.print(" (active-low), initial=");
+  Serial.println(raw ? "released" : "pressed");
+}
+
+static void handleRestartButton() {
+  if (!restartButtonEnabled) return;
+
+  unsigned long now = millis();
+  bool raw = digitalRead(PIN_RESTART_BUTTON);
+
+  if (raw != restartButtonLastRaw) {
+    restartButtonLastRaw = raw;
+    restartButtonLastEdgeMs = now;
+  }
+
+  if ((now - restartButtonLastEdgeMs) >= BUTTON_DEBOUNCE_MS && restartButtonStable != raw) {
+    restartButtonStable = raw;
+    bool pressed = !restartButtonStable; // active-low
+
+    if (pressed) {
+      restartButtonPressedSinceMs = now;
+      Serial.println("[Button] Restart button pressed");
+    } else {
+      Serial.println("[Button] Restart button released");
+      restartButtonPressedSinceMs = 0;
+      restartButtonArmed = true;
+    }
+  }
+
+  bool pressed = !restartButtonStable;
+  if (pressed && restartButtonArmed && restartButtonPressedSinceMs != 0 &&
+      (now - restartButtonPressedSinceMs) >= BUTTON_HOLD_RESTART_MS) {
+    restartButtonArmed = false;
+    Serial.println("[Button] Restart hold detected - rebooting");
+    delay(50);
+    ESP.restart();
+  }
+}
+
 struct ScheduleState {
   bool hasTime = false;
   bool sleeping = false;
@@ -234,6 +293,7 @@ void App::setup() {
 
   display.begin();
   display.showStatus("FacePlant", "Starting...");
+  initRestartButton();
 
   wifi.begin(settings, forceSetup);
 
@@ -245,7 +305,12 @@ void App::setup() {
 
   webhook.begin(settings);
 
-  web.begin(settings, wifi, moisture, face, webhook, bootMs);
+  {
+    MotionCalibration mc = settings.motionCalibration();
+    motion.setZeroOffsets(mc.rollZeroDeg, mc.pitchZeroDeg);
+  }
+
+  web.begin(settings, wifi, moisture, motion, face, webhook, bootMs);
   ota.begin(web.server(), &display);
 
   lastMood = face.mood();
@@ -259,6 +324,7 @@ void App::loop() {
   static unsigned long lastDisplayUpdate = 0;
 
   BootTrigger::clearAfterStableUptime();
+  handleRestartButton();
 
   wifi.loop();
   web.loop();