Add dynamic pages with clock, date, Home Assistant values and fonts

The hardcoded clock is now the built-in dynamic page "Clock". A dynamic page
has a background bitmap per time of day and up to 8 elements (clock, date,
Home Assistant value, text), each with position, alignment, font and overlay.
Pages are drawn on the ESP32, also for the web previews.

- Pages tab in the web UI: page editor with drag and drop, font upload
  (TTF/OTF converted in the browser to the FDF1 dot font format)
- Built-in fonts Small, Normal, Large and Full height (generated by
  tools/make_builtin_fonts.py), built-in bitmaps Pikachu and Pikachu yawning
- Home Assistant values over the REST API (URL and token in the HA tab)
- Settings version 4: evening settings removed (now time slots of the Clock
  page), old records are converted
- HA Mode dropdown lists the dynamic pages and bitmaps

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

src/esp32/main.cpp

@@ -3,13 +3,13 @@
 // The objects and the actions on them are in app.cpp; this file only sets the order.
 
 #include <Arduino.h>
-#include <time.h>
 
 #include "app.h"
 #include "config.h"
 #include "display/bitmap_store.h"
 #include "logic/status_led.h"
 #include "nano_link/nano_flash_bridge.h"
+#include "net/ha_api.h"
 #include "net/home_assistant.h"
 #include "net/wifi_ota.h"
 #include "system/boot_target.h"
@@ -79,15 +79,18 @@ void loop()
 	homeAssistantLoop();
 	webUiLoop();
 	appLoop();
+	// Home Assistant values of the shown page (can block about 3 s once a minute)
+	if (haApiLoop(wifiConnected()))
+		controller.pageChanged();
 
 	// While the Nano is being flashed, nothing else may talk to it
 	if (flashBridge.handle())
 		return;
 	status.loop(); // changed flip settings, once the display is on
 
-	struct tm now = {};
-	bool time_valid = getLocalTime(&now, 0);
-	controller.update(millis(), time_valid, now.tm_hour, now.tm_min, wifiConnected());
+	LocalTime now;
+	bool time_valid = appLocalTime(now);
+	controller.update(millis(), time_valid, now, wifiConnected());
 
 	bool led = appSettings().status_led && statusLedLevel(millis(), wifiConnected(), nano.isOn());
 	digitalWrite(LED_PIN, led);