Add periodic full refresh

src/screen.c

@@ -5,6 +5,8 @@
 *********************************************************/
 #include "screen.h"
 #include "lvgl/lvgl.h" // IWYU pragma: keep
+#include "lvgl/src/core/lv_obj_pos.h"
+#include "lvgl/src/display/lv_display.h"
 #include <stdint.h>
 #include <time.h>
 #include <unistd.h>
@@ -91,6 +93,11 @@ void cards_anim_cb(void *var, int32_t value)
 	lv_obj_set_style_text_opa(label_contactless, (int32_t)cards_opa, 0);
 }
 
+void screen_full_refresh(lv_timer_t *data)
+{
+	lv_obj_invalidate(lv_screen_active());
+}
+
 void screen_idle_update(lv_timer_t *data)
 {
 	time(&curr_time);
@@ -248,4 +255,7 @@ void screen_create(lv_obj_t *screen)
 
 	// timer to update clock
 	lv_timer_create(screen_idle_update, 100, NULL);
+
+	// timer to full refresh
+	lv_timer_create(screen_full_refresh, 5000, NULL);
 }