Add SDK RTC and IMU hardware abstraction support

Integrate SDK-based RTC and IMU backends as alternatives to direct hardware access. HalClock now attempts SDK RTC initialization and caches time values for reliability. HalTiltSensor adds SDK IMU backend with fallback logic. ClockOffsetActivity gains touch and swipe gesture support for field navigation.

lib/hal/HalClock.cpp

@@ -18,8 +18,11 @@ static uint8_t bcdToDec(uint8_t bcd) { return ((bcd >> 4) * 10) + (bcd & 0x0F);
 static uint8_t decToBcd(uint8_t dec) { return ((dec / 10) << 4) | (dec % 10); }
 
 void HalClock::begin() {
+  _usesSdkRtc = false;
   if (!gpio.deviceIsX3()) {
-    _available = false;
+    _available = _sdkRtc.begin();
+    _usesSdkRtc = _available;
+    LOG_INF("CLK", _available ? "SDK RTC found" : "RTC not found");
     return;
   }
 
@@ -57,6 +60,24 @@ bool HalClock::getTime(uint8_t& hour, uint8_t& minute) const {
     return true;
   }
 
+  if (_usesSdkRtc) {
+    Rtc::DateTime dt;
+    if (!_sdkRtc.now(dt)) {
+      if (!_hasCachedTime) return false;
+      _lastPollMs = now;
+      hour = _cachedHour;
+      minute = _cachedMinute;
+      return true;
+    }
+    _cachedHour = dt.hour;
+    _cachedMinute = dt.minute;
+    _lastPollMs = now;
+    _hasCachedTime = true;
+    hour = _cachedHour;
+    minute = _cachedMinute;
+    return true;
+  }
+
   // Read 3 bytes starting at register 0x00: seconds, minutes, hours
   Wire.beginTransmission(I2C_ADDR_DS3231);
   Wire.write(DS3231_SEC_REG);
@@ -131,6 +152,25 @@ bool HalClock::writeTimeToRTC(uint8_t hour, uint8_t minute, uint8_t second) {
   assert(hour < 24);
   assert(minute < 60);
   assert(second < 60);
+  if (_usesSdkRtc) {
+    Rtc::DateTime dt;
+    dt.hour = hour;
+    dt.minute = minute;
+    dt.second = second;
+    dt.year = 2000;
+    dt.month = 1;
+    dt.day = 1;
+    if (!_sdkRtc.set(dt)) {
+      LOG_ERR("CLK", "Failed to write time to SDK RTC");
+      return false;
+    }
+    _lastPollMs = 0;
+    _cachedHour = hour;
+    _cachedMinute = minute;
+    _hasCachedTime = true;
+    return true;
+  }
+
   Wire.beginTransmission(I2C_ADDR_DS3231);
   Wire.write(DS3231_SEC_REG);    // Start at register 0x00
   Wire.write(decToBcd(second));  // 0x00: Seconds
@@ -168,6 +208,27 @@ bool HalClock::syncFromNTP() {
       struct tm timeinfo;
       gmtime_r(&now, &timeinfo);
 
+      if (_usesSdkRtc) {
+        Rtc::DateTime dt;
+        dt.year = static_cast<uint16_t>(timeinfo.tm_year + 1900);
+        dt.month = static_cast<uint8_t>(timeinfo.tm_mon + 1);
+        dt.day = static_cast<uint8_t>(timeinfo.tm_mday);
+        dt.hour = static_cast<uint8_t>(timeinfo.tm_hour);
+        dt.minute = static_cast<uint8_t>(timeinfo.tm_min);
+        dt.second = static_cast<uint8_t>(timeinfo.tm_sec);
+        dt.weekday = static_cast<uint8_t>(timeinfo.tm_wday);
+        if (_sdkRtc.set(dt)) {
+          _lastPollMs = 0;
+          _cachedHour = dt.hour;
+          _cachedMinute = dt.minute;
+          _hasCachedTime = true;
+          LOG_INF("CLK", "RTC set to %04u-%02u-%02u %02u:%02u:%02u UTC", dt.year, dt.month, dt.day, dt.hour,
+                  dt.minute, dt.second);
+          return true;
+        }
+        return false;
+      }
+
       if (writeTimeToRTC(timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec)) {
         LOG_INF("CLK", "RTC set to %02d:%02d:%02d UTC", timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);
         return true;