Unify fullscreen/multiscreen/yes-no prompt message handling

Modify lcd_show_multiscreen_message_two_choices_and_wait_P to also
handle single-screen or empty (no-clear) prompts, making other functions
redundant. Saves 76 bytes.

Change existing functions to simply call
lcd_show_multiscreen_message_two_choices_and_wait_P with the correct
arguments.

This changes the prompt of existing Yes/No messages: the previous prompt
would use the last two lines of the LCD, while the new prompt is using
just the last line of the LCD instead.

Translation do not require updates, since the Yes/No translation was
already the same in both implementations.

Firmware/ultralcd.cpp

@@ -3177,7 +3177,7 @@ lcd_wait_for_click_delay(0);
 }
 
 //! @brief Show multiple screen message with yes and no possible choices and wait with possible timeout
-//! @param msg Message to show
+//! @param msg Message to show. If NULL, do not clear the screen and handle choice selection only.
 //! @param allow_timeouting if true, allows time outing of the screen
 //! @param default_yes if true, yes choice is selected by default, otherwise no choice is preselected
 //! @retval 1 yes choice selected by user
@@ -3187,8 +3187,21 @@ int8_t lcd_show_multiscreen_message_yes_no_and_wait_P(const char *msg, bool allo
 {
     return lcd_show_multiscreen_message_two_choices_and_wait_P(msg, allow_timeouting, default_yes, _T(MSG_YES), _T(MSG_NO));
 }
-//! @brief Show multiple screen message with two possible choices and wait with possible timeout
-//! @param msg Message to show
+//! @brief Show a two-choice prompt on the last line of the LCD
+//! @param first_selected Show first choice as selected if true, the second otherwise
+//! @param first_choice text caption of first possible choice
+//! @param second_choice text caption of second possible choice
+void lcd_show_two_choices_prompt_P(bool first_selected, const char *first_choice, const char *second_choice)
+{
+    lcd_set_cursor(0, 3);
+    lcd_print(first_selected? '>': ' ');
+    lcd_puts_P(first_choice);
+    lcd_set_cursor(7, 3);
+    lcd_print(!first_selected? '>': ' ');
+    lcd_puts_P(second_choice);
+}
+//! @brief Show single or multiple screen message with two possible choices and wait with possible timeout
+//! @param msg Message to show. If NULL, do not clear the screen and handle choice selection only.
 //! @param allow_timeouting if true, allows time outing of the screen
 //! @param default_first if true, fist choice is selected by default, otherwise second choice is preselected
 //! @param first_choice text caption of first possible choice
@@ -3199,15 +3212,18 @@ int8_t lcd_show_multiscreen_message_yes_no_and_wait_P(const char *msg, bool allo
 int8_t lcd_show_multiscreen_message_two_choices_and_wait_P(const char *msg, bool allow_timeouting, bool default_first,
         const char *first_choice, const char *second_choice)
 {
-	const char *msg_next = lcd_display_message_fullscreen_P(msg);
+	const char *msg_next = msg? lcd_display_message_fullscreen_P(msg) : NULL;
 	bool multi_screen = msg_next != NULL;
+
+    // Initial status/prompt on single-screen messages
 	bool yes = default_first ? true : false;
+	if (!msg_next) lcd_show_two_choices_prompt_P(yes, first_choice, second_choice);
 
 	// Wait for user confirmation or a timeout.
 	unsigned long previous_millis_cmd = _millis();
-	int8_t        enc_dif = lcd_encoder_diff;
+	int8_t enc_dif = lcd_encoder_diff;
 	lcd_consume_click();
-	//KEEPALIVE_STATE(PAUSED_FOR_USER);
+	KEEPALIVE_STATE(PAUSED_FOR_USER);
 	for (;;) {
 		for (uint8_t i = 0; i < 100; ++i) {
 			delay_keep_alive(50);
@@ -3218,19 +3234,13 @@ int8_t lcd_show_multiscreen_message_two_choices_and_wait_P(const char *msg, bool
 
 			if (abs(enc_dif - lcd_encoder_diff) > 4) {
 				if (msg_next == NULL) {
-					lcd_set_cursor(0, 3);
-					if (enc_dif < lcd_encoder_diff && yes) {
-						lcd_print(' ');
-						lcd_putc_at(7, 3, '>');
-						yes = false;
-						Sound_MakeSound(e_SOUND_TYPE_EncoderMove);
-					}
-					else if (enc_dif > lcd_encoder_diff && !yes) {
-						lcd_print('>');
-						lcd_putc_at(7, 3, ' ');
-						yes = true;
-						Sound_MakeSound(e_SOUND_TYPE_EncoderMove);
-					}
+                    if ((enc_dif < lcd_encoder_diff && yes) ||
+                        ((enc_dif > lcd_encoder_diff && !yes)))
+                    {
+                        yes = !yes;
+                        lcd_show_two_choices_prompt_P(yes, first_choice, second_choice);
+                        Sound_MakeSound(e_SOUND_TYPE_EncoderMove);
+                    }
 					enc_dif = lcd_encoder_diff;
 				}
 				else {
@@ -3241,7 +3251,7 @@ int8_t lcd_show_multiscreen_message_two_choices_and_wait_P(const char *msg, bool
 			if (lcd_clicked()) {
 				Sound_MakeSound(e_SOUND_TYPE_ButtonEcho);
 				if (msg_next == NULL) {
-					//KEEPALIVE_STATE(IN_HANDLER);
+					KEEPALIVE_STATE(IN_HANDLER);
 					lcd_set_custom_characters();
 					return yes;
 				}
@@ -3255,17 +3265,12 @@ int8_t lcd_show_multiscreen_message_two_choices_and_wait_P(const char *msg, bool
 			msg_next = lcd_display_message_fullscreen_P(msg_next);
 		}
 		if (msg_next == NULL) {
-			lcd_set_cursor(0, 3);
-			if (yes) lcd_print('>');
-			lcd_puts_at_P(1, 3, first_choice);
-			lcd_set_cursor(7, 3);
-			if (!yes) lcd_print('>');
-			lcd_puts_at_P(8, 3, second_choice);
+            lcd_show_two_choices_prompt_P(yes, first_choice, second_choice);
 		}
 	}
 }
 
-//! @brief Display and wait for a Yes/No choice using the last two lines of the LCD
+//! @brief Display and wait for a Yes/No choice using the last line of the LCD
 //! @param allow_timeouting if true, allows time outing of the screen
 //! @param default_yes if true, yes choice is selected by default, otherwise no choice is preselected
 //! @retval 1 yes choice selected by user
@@ -3273,60 +3278,11 @@ int8_t lcd_show_multiscreen_message_two_choices_and_wait_P(const char *msg, bool
 //! @retval -1 screen timed out
 int8_t lcd_show_yes_no_and_wait(bool allow_timeouting, bool default_yes)
 {
-	if (default_yes) {
-		lcd_putc_at(0, 2, '>');
-		lcd_puts_P(_T(MSG_YES));
-		lcd_puts_at_P(1, 3, _T(MSG_NO));
-	}
-	else {
-		lcd_puts_at_P(1, 2, _T(MSG_YES));
-		lcd_putc_at(0, 3, '>');
-		lcd_puts_P(_T(MSG_NO));
-	}
-	int8_t retval = default_yes ? true : false;
-
-	// Wait for user confirmation or a timeout.
-	unsigned long previous_millis_cmd = _millis();
-	int8_t        enc_dif = lcd_encoder_diff;
-	lcd_consume_click();
-	KEEPALIVE_STATE(PAUSED_FOR_USER);
-	for (;;) {
-		if (allow_timeouting && _millis() - previous_millis_cmd > LCD_TIMEOUT_TO_STATUS)
-		{
-		    retval = -1;
-		    break;
-		}
-		manage_heater();
-		manage_inactivity(true);
-		if (abs(enc_dif - lcd_encoder_diff) > 4) {
-			lcd_set_cursor(0, 2);
-				if (enc_dif < lcd_encoder_diff && retval) {
-					lcd_print(' ');
-					lcd_putc_at(0, 3, '>');
-					retval = 0;
-					Sound_MakeSound(e_SOUND_TYPE_EncoderMove);
-
-				}
-				else if (enc_dif > lcd_encoder_diff && !retval) {
-					lcd_print('>');
-					lcd_putc_at(0, 3, ' ');
-					retval = 1;
-					Sound_MakeSound(e_SOUND_TYPE_EncoderMove);
-				}
-				enc_dif = lcd_encoder_diff;
-		}
-		if (lcd_clicked()) {
-			Sound_MakeSound(e_SOUND_TYPE_ButtonEcho);
-			KEEPALIVE_STATE(IN_HANDLER);
-			break;
-		}
-	}
-    lcd_encoder_diff = 0;
-    return retval;
+    return lcd_show_multiscreen_message_yes_no_and_wait_P(NULL, allow_timeouting, default_yes);
 }
 
 //! @brief Show single screen message with yes and no possible choices and wait with possible timeout
-//! @param msg Message to show
+//! @param msg Message to show. If NULL, do not clear the screen and handle choice selection only.
 //! @param allow_timeouting if true, allows time outing of the screen
 //! @param default_yes if true, yes choice is selected by default, otherwise no choice is preselected
 //! @retval 1 yes choice selected by user
@@ -3335,8 +3291,7 @@ int8_t lcd_show_yes_no_and_wait(bool allow_timeouting, bool default_yes)
 //! @relates lcd_show_yes_no_and_wait
 int8_t lcd_show_fullscreen_message_yes_no_and_wait_P(const char *msg, bool allow_timeouting, bool default_yes)
 {
-    lcd_display_message_fullscreen_P(msg);
-    return lcd_show_yes_no_and_wait(allow_timeouting, default_yes);
+    return lcd_show_multiscreen_message_yes_no_and_wait_P(msg, allow_timeouting, default_yes);
 }
 
 void lcd_bed_calibration_show_result(BedSkewOffsetDetectionResultType result, uint8_t point_too_far_mask)