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/text.cpp

@@ -0,0 +1,33 @@
+#include "display/text.h"
+
+#include <string.h>
+
+static const int CHAR_WIDTH = 6;
+
+static void drawCentered(BROSE9323 &display, const char *text, int y)
+{
+	int len = strlen(text);
+	if (len > TEXT_LINE_CHARS)
+		len = TEXT_LINE_CHARS;
+	char line[TEXT_LINE_CHARS + 1];
+	memcpy(line, text, len);
+	line[len] = '\0';
+
+	display.setCursor((display.width() - len * CHAR_WIDTH) / 2, y);
+	display.print(line);
+}
+
+void drawTextLines(BROSE9323 &display, const char *line1, const char *line2)
+{
+	display.fillScreen(0);
+	display.setTextSize(1);
+	display.setTextWrap(false);
+	display.setTextColor(1);
+	if (line2 == nullptr || line2[0] == '\0')
+	{
+		drawCentered(display, line1, 6); // one line: vertically centered
+		return;
+	}
+	drawCentered(display, line1, 1);
+	drawCentered(display, line2, 10);
+}