Harden nRF52 OTA, USB sessions, and T096 controls

Bind Companion replies to request transports, make dual-CDC USB sessions nonblocking and reconnect-safe, and harden nRF52 watchdog/OTA storage paths. Fix T096 button debounce, display wake, sleep races, and the compact message layout; add exact WisBlock OTA profiles plus expanded native/static/HIL documentation.

src/helpers/UsbLoggingLineStateOverride.cpp

@@ -0,0 +1,58 @@
+// Include only TinyUSB's CDC protocol types here. cdc_device.h and the Arduino
+// TinyUSB headers declare these callbacks weak, and that attribute would carry
+// onto our definitions. This translation unit intentionally supplies the
+// strong callbacks which override Adafruit's weak defaults for nRF52 USB
+// Companion builds. CDC0 needs exact close events even on single-CDC targets;
+// dual-CDC builds additionally forward CDC1 reconnect events.
+#if defined(ARDUINO) && defined(NRF52_PLATFORM) \
+    && defined(ENABLE_USB_INTERFACE)
+#include <class/cdc/cdc.h>
+
+extern "C" void meshTinyUsbCdcLineStateChanged(uint8_t instance, bool dtr,
+                                                bool rts);
+extern "C" void meshTinyUsbCdcLineCodingChanged(uint8_t instance);
+extern "C" void meshTinyUsbDeviceSessionBoundary();
+#if defined(MESH_DUAL_CDC_LOGGING)
+extern "C" void meshTinyUsbStartOfFrame(uint32_t frame_count);
+// cdc_device.h would attach TinyUSB's weak callback declarations to the strong
+// overrides in this translation unit. Declare only the non-callback API used
+// below, retaining the exact TinyUSB signature without importing that header.
+extern "C" uint32_t tud_cdc_n_write_flush(uint8_t itf);
+
+// The nRF core calls this weak hook from both the application task and the
+// TinyUSB task. Never let those application-side yield()/delay() calls touch
+// CDC1; its SOF bridge below is the sole endpoint owner. CDC0 retains the
+// framework's ordinary opportunistic flush behavior.
+extern "C" void TinyUSB_Device_FlushCDC(void) {
+  (void)tud_cdc_n_write_flush(0);
+}
+#endif
+
+// TinyUSB calls unmount for a hard unplug/configuration loss, but not for an
+// ordinary bus-reset event. The subsequent mount is therefore also a session
+// boundary; the forwarded handler is edge-sensitive so initial enumeration
+// and an unmount/mount pair count at most once.
+extern "C" void tud_mount_cb(void) {
+  meshTinyUsbDeviceSessionBoundary();
+}
+
+extern "C" void tud_umount_cb(void) {
+  meshTinyUsbDeviceSessionBoundary();
+}
+
+extern "C" void tud_cdc_line_state_cb(uint8_t instance, bool dtr, bool rts) {
+  meshTinyUsbCdcLineStateChanged(instance, dtr, rts);
+}
+
+extern "C" void tud_cdc_line_coding_cb(uint8_t instance,
+                                        cdc_line_coding_t const* line_coding) {
+  (void)line_coding;
+  meshTinyUsbCdcLineCodingChanged(instance);
+}
+
+#if defined(MESH_DUAL_CDC_LOGGING)
+extern "C" void tud_sof_cb(uint32_t frame_count) {
+  meshTinyUsbStartOfFrame(frame_count);
+}
+#endif
+#endif