Merge upstream dev through 5846fa19

Import Airoha GPS RTC backup sleep, 24 contact search results, and the T-Echo Lite USB companion target. Preserve existing GPS telemetry and power-saving controls, crypto alignment checks, ESP32 RTC recovery, and RAK11310 dynamic-preference compatibility.

Validate GPS sleep acknowledgments with their NMEA checksum and add six native regression tests covering retry, drain, corruption, grace timeout, and timer rollover.

Verified: 1648 native and KISS modem tests; targeted nRF52, companion routing, one-key DM, and clock checks; T1000-E BLE, MeshTracker X1 USB, and T-Echo Lite USB companion builds.

test/mocks/Arduino.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <cstdint>
+#include <ctype.h>
 #include <cmath>
 #include <cstdio>
 #include <cstdlib>

test/test_airoha_sleep/RTClib.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <stdint.h>
+
+// Command/ACK tests do not use RTC conversion. Keep the provider header
+// compilable without the hardware I2C dependencies of the Arduino RTC library.
+class DateTime {
+public:
+  DateTime(uint16_t, uint8_t, uint8_t, uint8_t, uint8_t, uint8_t) {}
+  uint32_t unixtime() const { return 0; }
+};

test/test_airoha_sleep/test_airoha_sleep.cpp

@@ -0,0 +1,109 @@
+#include <gtest/gtest.h>
+#include <Arduino.h>
+#include <deque>
+#include <string>
+#include <vector>
+
+void yield() { ++g_mock_millis; }
+
+#include <helpers/sensors/MicroNMEALocationProvider.h>
+#include <helpers/sensors/AirohaSleep.h>
+
+// The production provider overrides this default virtual command sender.
+void LocationProvider::sendSentence(const char*) {}
+
+class GpsStream : public Stream {
+public:
+  std::deque<uint8_t> incoming;
+  std::vector<std::string> commands;
+  std::string pending_command;
+  unsigned reply_on_attempt = 0;
+  bool send_ready = true;
+
+  void receive(const char* text) {
+    while (*text) incoming.push_back(static_cast<uint8_t>(*text++));
+  }
+  int available() override { return static_cast<int>(incoming.size()); }
+  int read() override {
+    if (incoming.empty()) return -1;
+    uint8_t c = incoming.front();
+    incoming.pop_front();
+    return c;
+  }
+  size_t write(uint8_t c) override {
+    pending_command += static_cast<char>(c);
+    if (c == '\n') {
+      commands.push_back(pending_command);
+      pending_command.clear();
+      if (reply_on_attempt != 0 && commands.size() == reply_on_attempt) {
+        receive("$PAIR001,650,0*38\r\n");
+        if (send_ready) receive("$PAIR650,0*25\r\n");
+      }
+    }
+    return 1;
+  }
+};
+
+TEST(AirohaSleep, RejectsCorruptedAcknowledgment) {
+  resetArduinoMock();
+  GpsStream uart;
+  MicroNMEALocationProvider gps(uart, nullptr, -1, -1);
+  uart.receive("$PAIR001,650,0*00\r\n");
+  EXPECT_FALSE(gps.waitFor("$PAIR001,650,0", 50));
+  EXPECT_EQ(50U, millis());
+}
+
+TEST(AirohaSleep, ValidAcknowledgmentAfterCorruptedSentenceIsAccepted) {
+  resetArduinoMock();
+  GpsStream uart;
+  MicroNMEALocationProvider gps(uart, nullptr, -1, -1);
+  uart.receive("$PAIR001,650,0*00\r\n$PAIR001,650,0*38\r\n");
+  EXPECT_TRUE(gps.waitFor("$PAIR001,650,0", 50));
+}
+
+TEST(AirohaSleep, RetriesAndDrainsStaleAcknowledgments) {
+  resetArduinoMock();
+  GpsStream uart;
+  uart.reply_on_attempt = 3;
+  uart.receive("$PAIR001,650,0*38\r\n"); // Must not acknowledge a new command.
+  MicroNMEALocationProvider gps(uart, nullptr, -1, -1);
+  ASSERT_TRUE(airohaEnterSleep(&gps));
+  ASSERT_EQ(3U, uart.commands.size());
+  for (const auto& command : uart.commands) EXPECT_EQ("$PAIR650,0*25\r\n", command);
+  EXPECT_EQ(100U, millis());
+}
+
+TEST(AirohaSleep, MissingReceiverIsBoundedToThreeAttempts) {
+  resetArduinoMock();
+  GpsStream uart;
+  uart.receive("$PAIR001,650,0*38\r\n");
+  MicroNMEALocationProvider gps(uart, nullptr, -1, -1);
+  EXPECT_FALSE(airohaEnterSleep(&gps));
+  EXPECT_EQ(3U, uart.commands.size());
+  EXPECT_EQ(150U, millis());
+}
+
+TEST(AirohaSleep, AcceptedCommandAllowsBoundedReadyGrace) {
+  resetArduinoMock();
+  GpsStream uart;
+  uart.reply_on_attempt = 1;
+  uart.send_ready = false;
+  MicroNMEALocationProvider gps(uart, nullptr, -1, -1);
+  EXPECT_TRUE(airohaEnterSleep(&gps));
+  EXPECT_EQ(1U, uart.commands.size());
+  EXPECT_EQ(50U, millis());
+}
+
+TEST(AirohaSleep, TimeoutWorksAcrossMillisRollover) {
+  resetArduinoMock();
+  g_mock_millis = UINT32_MAX - 10;
+  GpsStream uart;
+  MicroNMEALocationProvider gps(uart, nullptr, -1, -1);
+  EXPECT_FALSE(gps.waitFor("$PAIR001,650,0", 50));
+  EXPECT_EQ(39U, millis());
+}
+
+int main(int argc, char** argv) {
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}