Show status messages on the display

- Clock firmware: 'Connecting to WiFi...' and 'Getting the time...' at
  boot, 'Crashed!' in the OTA-only modes, and 'No WiFi' with the time
  when WiFi is down for over a minute (new DisplayController screen)
- Recovery app: shows its reason, the setup WiFi name, or its IP address,
  then powers the display off (flipdots keep the image)
- StatusScreen and drawTextLines shared by both apps
- Driver: ESP begin() no longer draws 'ESP Connected'
- Tests: No WiFi screen, short reason texts (70 total)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/esp32/display/status_screen.cpp

@@ -0,0 +1,31 @@
+#include "display/status_screen.h"
+
+#include <Arduino.h>
+
+#include "config.h"
+#include "display/text.h"
+
+StatusScreen::StatusScreen(BROSE9323 &display, NanoLink &nano) : _display(display), _nano(nano)
+{
+}
+
+void StatusScreen::show(const char *line1, const char *line2, bool keep_on)
+{
+	Serial.printf("Display: %s / %s\n", line1, line2 ? line2 : "");
+	_nano.on();
+	if (!_started)
+	{
+		_display.begin(&_nano.stream());
+		_display.setTiming(FLIP_TIME);
+		_started = true;
+	}
+	drawTextLines(_display, line1, line2);
+	_display.display();
+
+	if (!keep_on)
+	{
+		// The first frame after power on flips every dot, give the Nano time for that
+		delay(STATUS_FLIP_TIME);
+		_nano.off();
+	}
+}