Fix Gemini voice genders in books 9-12 (achernar is a female voice)

Male-described speakers were mapped to the female voice achernar (and a few
females to schedar) — 210 VOICE swaps across the four regenerated books.
Also: book-11 'Two Letters' now labeled Jane:/Ann: with female voices
instead of one Narrator (Yana's report), and junk auto-declared 'VOICE: ID'
lines dropped.

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

book-11-lesson-2.module

@@ -6,38 +6,37 @@ HOME_LANG_G: en
 VOICE_DEFAULT: aoede | Clear, friendly American English narrator
 VOICE_PROMPT: gacrux | Questions and cues, read clearly
 VOICE_RESPONSE: schedar | Model answers, warm and clear
-VOICE: Carl | achernar | Male student driver
+VOICE: Carl | achird | Male student driver
 VOICE: Mr_Ford | schedar | Male driving instructor
 VOICE: Lynn | aoede | Female speaker
 VOICE: Instructor | achird | Male driving instructor
-VOICE: Waiter | achernar | Male speaker
+VOICE: Waiter | schedar | Male speaker
 VOICE: Martin | achird | Male speaker
 VOICE: Martha | aoede | Female speaker
-VOICE: Morton | achernar | Male speaker
+VOICE: Morton | achird | Male speaker
 VOICE: Marian | aoede | Female speaker
-VOICE: James | achernar | Male speaker
+VOICE: James | charon | Male speaker
 VOICE: Ralph | achird | Male speaker
-VOICE: StudentA | achernar | Male student
+VOICE: StudentA | achird | Male student
 VOICE: StudentB | aoede | Female student
 VOICE: Kathy | gacrux | Female speaker
-VOICE: Kevin | achernar | Male speaker
+VOICE: Kevin | achird | Male speaker
 VOICE: Sally | gacrux | Female speaker
-VOICE: Steve | achernar | Male speaker
+VOICE: Steve | schedar | Male speaker
 VOICE: Maria | gacrux | Female speaker
-VOICE: David | achernar | Male speaker
+VOICE: David | achird | Male speaker
 VOICE: Janet | gacrux | Female speaker
-VOICE: Jason | achernar | Male speaker
+VOICE: Jason | schedar | Male speaker
 VOICE: Alice | gacrux | Female speaker
-VOICE: Larry | achernar | Male speaker
+VOICE: Larry | schedar | Male speaker
 VOICE: Jan | gacrux | Female speaker
-VOICE: Bob | achernar | Male speaker
-VOICE: Tom | achernar | Male speaker
+VOICE: Bob | achird | Male speaker
+VOICE: Tom | charon | Male speaker
 VOICE: Ann | gacrux | Female speaker
-VOICE: Keith | achernar | Male speaker
+VOICE: Keith | schedar | Male speaker
 VOICE: Frank | achird | Male speaker
-VOICE: Man | achernar | Male speaker
+VOICE: Man | achird | Male speaker
 VOICE: Woman | gacrux | Female speaker
-VOICE: ID | achernar | speaker (auto)
 VOICE: Narrator | achird | speaker (auto)
 
 $SESSION 2-1: Carl Learns to Drive