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/recovery/main.cpp

@@ -1,16 +1,19 @@
 // Recovery app (factory partition): WiFi setup portal and OTA, nothing else. Started when
 // the clock firmware can't connect to WiFi, crashes repeatedly, after quick power cycles,
 // from the Home Assistant button, or by the bootloader when no clock firmware works.
-// It never drives the display. See README.md "Recovery app".
+// It only shows short status messages on the display. See README.md "Recovery app".
 
 #include <Arduino.h>
 #include <ArduinoOTA.h>
 #include <WiFi.h>
 #include <esp_task_wdt.h>
 
+#include "BROSE9323.h"
 #include "config.h"
 #include "credentials.h"
+#include "display/status_screen.h"
 #include "logic/boot_policy.h"
+#include "nano_link/nano_link.h"
 #include "recovery_state.h"
 #include "system/boot_target.h"
 #include "system/system_store.h"
@@ -21,9 +24,25 @@ static const uint32_t STATION_RETRY_TIME = 30000;
 // Close the setup AP this long after the stored WiFi works again
 static const uint32_t AP_CLOSE_DELAY = 120000;
 static const uint32_t RECOVERY_WATCHDOG_S = 60;
+// Show a new status at most this often (each message power cycles the display)
+static const uint32_t STATUS_MIN_INTERVAL = 30000;
 
 RecoveryState recovery;
 
+static NanoLink nano(Serial2, NANO_RX_PIN, NANO_TX_PIN, RELAY_PIN, NANO_RESET_PIN);
+static BROSE9323 display(DISPLAY_WIDTH, DISPLAY_HEIGHT, PANEL_WIDTH);
+static StatusScreen status(display, nano);
+
+enum class Shown
+{
+	Nothing,
+	Started,   // "Recovery" + reason
+	SetupWifi, // name of the setup WiFi
+	Connected, // IP address
+};
+static Shown shown = Shown::Nothing;
+static uint32_t last_status = 0;
+
 static uint32_t station_lost_since = 0;
 static uint32_t station_connected_since = 0;
 static bool watchdog_running = false;
@@ -79,6 +98,32 @@ static void updateWifi()
 		connectStation();
 }
 
+// Show what is going on, so you know what to do without a computer. The display is
+// switched off after each message; the dots keep showing it.
+static void updateDisplay()
+{
+	Shown wanted = WiFi.status() == WL_CONNECTED ? Shown::Connected
+				   : recovery.ap_running          ? Shown::SetupWifi
+												  : Shown::Started;
+	if (wanted == shown || (shown != Shown::Nothing && millis() - last_status < STATUS_MIN_INTERVAL))
+		return;
+	shown = wanted;
+	last_status = millis();
+
+	switch (wanted)
+	{
+	case Shown::Connected:
+		status.show("Recovery", WiFi.localIP().toString().c_str());
+		break;
+	case Shown::SetupWifi:
+		status.show("WiFi setup:", SETUP_AP_SSID);
+		break;
+	default:
+		status.show("Recovery", recoveryReasonShort(recovery.reason));
+		break;
+	}
+}
+
 // Double blink: recovery app is running
 static void updateLed()
 {
@@ -91,11 +136,8 @@ void setup()
 	Serial.begin(115200);
 	Serial.println("FlipDot recovery app");
 
-	// Display off: relay off, and no high TX line that would power the Nano
-	digitalWrite(RELAY_PIN, HIGH);
-	pinMode(RELAY_PIN, OUTPUT);
-	pinMode(NANO_TX_PIN, INPUT);
 	pinMode(LED_PIN, OUTPUT);
+	nano.begin(); // display off between status messages
 
 	recovery.reason = takeRecoveryReason();
 	main_available = mainFirmwareAvailable();
@@ -123,6 +165,7 @@ void setup()
 	ArduinoOTA.begin();
 
 	portalBegin();
+	updateDisplay();
 
 	// A hang restarts the ESP32; the bootloader then starts this recovery app again
 	esp_task_wdt_init(RECOVERY_WATCHDOG_S, true);
@@ -138,6 +181,7 @@ void loop()
 	ArduinoOTA.handle();
 	portalLoop();
 	updateWifi();
+	updateDisplay();
 	updateLed();
 
 	bool wifi_connected = WiFi.status() == WL_CONNECTED;