1A: refined clip timings (cue trimming, gap compression), 512px recomposed images, four Figure-8 panels, activity-wide Figure-5 map; SHOW_PROMPT migration + INTRO fixes for remaining lessons

Co-authored-by: Cursor <cursoragent@cursor.com>

lesson-1D.module

@@ -13,7 +13,7 @@ VOICE: Sam | gacrux
 $LESSON Lesson 1D
 
 $DIALOGUE Figure 1: Listen to the dialog
-INTRO: Look at Figure 1. Listen to a dialogue.
+INTRO: You're going to hear a dialogue. Listen carefully.
 
 Speaker1: What languages does Jack speak? {bk04-l1d-f1-02.mp3}
 
@@ -105,7 +105,7 @@ LINE: repeat {bk04-l1d-f3-07.mp3}
 LINE: leave {bk04-l1d-f4-01.mp3}
 
 $DIALOGUE Figure 4: Listen and repeat the dialog
-INTRO: Look at figure four. Listen to the dialogue.
+INTRO: You're going to hear another dialogue. Listen carefully.
 REPEAT
 
 Jim: What do you do on weekends? {bk04-l1d-f4-02.mp3}
@@ -126,7 +126,6 @@ Sam: All right. {bk04-l1d-f4-09.mp3}
 
 $SELECT Figure 5: Circle the correct answer
 INSTRUCTION: Tap Yes or No.
-AUDIO_ONLY
 OPTION: a | Yes
 OPTION: b | No
 
@@ -158,7 +157,6 @@ ANSWER: a
 
 $SELECT Figure 6: Write A, B, or C on the lines
 INSTRUCTION: Listen to the word and tap A, B, or C based on the ending sound.
-AUDIO_ONLY
 OPTION: a | A /d/ played
 OPTION: b | B /t/ worked
 OPTION: c | C /Id/ wanted