Merge upstream/main (v1.16.0) into wio-unified

Merge 254 upstream commits. Highlights relevant to the Wio fork: native
NRF52 companion power-saving (sleep when !hasPendingWork), preamble 16->32
for SF<9, generic sensor-registration model, CMD_SEND_RAW_PACKET, isEink()
display abstraction, KEEP_DISPLAY_ON_USB, contacts-sync/transient fixes.

Conflicts resolved (11 files):
- buzzer.h/.cpp: keep NRF52 include guard + our begin()->startup(); fold in
  upstream doc comment.
- platformio (wio + eink): keep our slim env layout, add upstream kiss_modem
  env (+ debug_tool=stlink on eink ble).
- GxEPDDisplay.h: take upstream isEink() override.
- EnvironmentSensorManager.h: take upstream's wider #if guard.
- DataStore.cpp: take upstream saveContacts(filter) signature, keep our
  ::openWrite (member openWrite would shadow the global 2-arg overload).
- main.cpp: keep our watchdog init + add board.onBootComplete(); adopt
  upstream's `if(!hasPendingWork()) sleep` loop.
- MyMesh.h: version -> v1.16-solo.0, build date 6 Jun 2026.
- MyMesh.cpp: keep both CMD codes (SCREENSHOT 66 + RAW_PACKET 65), both field
  inits, both handlers, our screenshot fns + upstream saveContacts/save_filter,
  upstream hasPendingWork() + our MyMeshBot include.
- UITask.cpp: keep our solo splash/clock page/snprintf/buzzer init; merge
  auto-off (+ opt-in KEEP_DISPLAY_ON_USB); merge low-batt shutdown (our EMA +
  prefs threshold + upstream's !isExternalPowered() guard and eink-aware delay).

Post-merge drift fixes (upstream API/architecture changes, not conflicts):
- applyTxPower(): radio_set_tx_power() removed upstream -> radio_driver.setTxPower().
- Sensor refactor dropped the per-sensor *_initialized flags our
  getAvailableLPPTypes() relied on; removed that override and the SENSORS page
  now derives available LPP types from the populated sensors_lpp buffer.

README kept ours via .gitattributes merge=ours. Builds verified on all 5 Wio
envs (dual, eink dual, radio_ble, dual_dev, eink_dual_dev). Not yet
hardware-verified.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/companion_radio/main.cpp

@@ -108,6 +108,12 @@ void halt() {
   while (1) ;
 }
 
+/* WIFI RECONNECT TRACKERS */
+#if defined(ESP32) && defined(WIFI_SSID)
+  bool wifi_needs_reconnect = false;
+  unsigned long last_wifi_reconnect_attempt = 0;
+#endif
+
 void setup() {
   Serial.begin(115200);
 
@@ -128,7 +134,7 @@ void setup() {
 
   if (!radio_init()) { halt(); }
 
-  fast_rng.begin(radio_get_rng_seed());
+  fast_rng.begin(radio_driver.getRngSeed());
 
 #if defined(NRF52_PLATFORM) || defined(STM32_PLATFORM)
   InternalFS.begin();
@@ -200,6 +206,18 @@ void setup() {
 
 #ifdef WIFI_SSID
   board.setInhibitSleep(true);   // prevent sleep when WiFi is active
+  WiFi.setAutoReconnect(true);
+
+  WiFi.onEvent([](WiFiEvent_t event, WiFiEventInfo_t info){
+      if (event == ARDUINO_EVENT_WIFI_STA_DISCONNECTED) {
+          WIFI_DEBUG_PRINTLN("WiFi disconnected. Flagging for reconnect...");
+          wifi_needs_reconnect = true;
+      } else if (event == ARDUINO_EVENT_WIFI_STA_GOT_IP) {
+          WIFI_DEBUG_PRINTLN("WiFi connected successfully!");
+          wifi_needs_reconnect = false;
+      }
+  });
+
   WiFi.begin(WIFI_SSID, WIFI_PWD);
   serial_interface.begin(TCP_PORT);
 #elif defined(BLE_PIN_CODE)
@@ -237,6 +255,7 @@ void setup() {
   NRF_WDT->RREN        = 0x01;        // enable reload register 0
   NRF_WDT->TASKS_START = 1;
 #endif
+  board.onBootComplete();
 }
 
 void loop() {
@@ -249,5 +268,22 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
-  board.sleep(0);  // CPU sleeps until next interrupt (radio, timer, BLE); nRF52 ignores the seconds param
+
+  // CPU sleeps until next interrupt (radio, timer, BLE) — but only when the
+  // mesh has no pending work, so queued TX/processing isn't delayed.
+  if (!the_mesh.hasPendingWork()) {
+#if defined(NRF52_PLATFORM)
+    board.sleep(0); // nrf ignores seconds param, sleeps whenever possible
+#endif
+  }
+
+#if defined(ESP32) && defined(WIFI_SSID)
+  // Safely attempt to reconnect every 10 seconds if flagged
+  if (wifi_needs_reconnect && (millis() - last_wifi_reconnect_attempt > 10000)) {
+    WIFI_DEBUG_PRINTLN("Attempting manual WiFi reconnect...");
+    WiFi.disconnect();
+    WiFi.reconnect();
+    last_wifi_reconnect_attempt = millis();
+  }
+#endif
 }