vocab: stop re-teaching a word later in the same session (239 tags)

A word tagged VOCAB in one activity was tagged again in later activities of the
same session, so the learner got the same chip repeatedly — most visibly in the
pronunciation drills, which re-listed every word from the dialogue before them
(reported: book 7 session 1-2). Rule applied: drop a VOCAB whose word was
already tagged in an EARLIER activity of that session. Repeats INSIDE one
activity are kept — those teach distinct senses ('stuck to his finger' vs
'stuck the milk in the fridge', 'shop' as verb then noun). Also dropped chips
for plurals of already-known words in book 7 session 1-2, where the drill
teaches the singular/plural pair rather than new vocabulary. No session lost
all of its vocabulary (verified).

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

book-3-lesson-1.module

@@ -64,13 +64,10 @@ INTRO: Now the first three of those words on their own, from the tape. Listen cl
 INSTRUCTION: Listen and repeat.
 REPEAT
 
-VOCAB: morning
 LINE: Morning. {page_009_001.jpg} {bk03-l1a-f1-01.mp3}
 
-VOCAB: noon
 LINE: Noon. {page_009_002.jpg} {bk03-l1a-f1-02.mp3}
 
-VOCAB: afternoon
 LINE: Afternoon. {page_009_003.jpg} {bk03-l1a-f1-03.mp3}
 
 # Source: LLA 1A Figure 1
@@ -128,13 +125,10 @@ INTRO: The day isn't over yet. Here are the words for the later hours — listen
 INSTRUCTION: Listen and repeat.
 REPEAT
 
-VOCAB: evening
 LINE: Evening. {page_010_001.jpg} {bk03-l1a-f2-01.mp3}
 
-VOCAB: night
 LINE: Night. {page_010_002.jpg} {bk03-l1a-f2-02.mp3}
 
-VOCAB: midnight
 LINE: Midnight. {page_010_003.jpg} {bk03-l1a-f2-03.mp3}
 
 # Source: LLA 1A Figure 2
@@ -235,13 +229,10 @@ LINE: We study every day. {bk03-l1a-f2-18.mp3}
 VOCAB: late
 LINE: He goes to class late. {bk03-l1a-f2-19.mp3}
 
-VOCAB: hungry
 LINE: He's hungry. He's eating an orange. {bk03-l1a-f2-20.mp3}
 
-VOCAB: snack
 LINE: He's eating a snack before dinner. {bk03-l1a-f2-21.mp3}
 
-VOCAB: thirsty
 LINE: She's thirsty. She's drinking water. {bk03-l1a-f2-22.mp3}
 
 # Source: LLA 1A Figure 3