Add dotted rhythms to iconic songs for musical accuracy

- Silent Night: proper 6/8 feel with dotted-quarter + eighth (3,1,2) pattern
- Deck the Halls: dotted pickup on "Deck the halls" and "Fa la la" phrases
- Amazing Grace: dotted quarter-eighth pairs in "A-MAZ-ing Grace" phrasing
- Auld Lang Syne: characteristic dotted Scots snap rhythm (3,1 pattern)

https://claude.ai/code/session_01MhCcEPfX3JqAk8zmvLXZ1g

index.html

@@ -3626,12 +3626,12 @@ const CHRISTMAS_PIECES=(function(){
   var silent=carol("Silent Night","F. Gruber (1818)",72,
     [G4,A4,G4,E4,G4,A4,G4,E4,D5,D5,B4,C5,C5,G4,A4,A4,C5,B4,A4,G4,A4,G4,E4,A4,A4,C5,B4,A4,G4,A4,G4,E4,D5,D5,F5,D5,B4,C5,E5,C5,G4,E4,G4,F4,D4,C4],
     [3,0,3,2,3,0,3,2,0,0,3,0,0,3,0,0,0,3,0,3,0,3,2,0,0,0,3,0,3,0,3,2,0,0,1,0,3,0,2,0,3,2,3,1,1,0],
-    [2,2,2,4,2,2,2,4,2,2,4,2,2,4,2,2,2,2,2,2,2,2,4,2,2,2,2,2,2,2,2,4,2,2,2,2,4,2,2,2,2,2,2,2,2,4],
+    [3,1,2,6,3,1,2,6,2,2,6,2,2,6,2,2,3,1,2,3,1,2,6,2,2,3,1,2,3,1,2,6,2,2,3,1,6,2,2,2,2,2,3,1,2,6],
     3,C4);
   var deck=carol("Deck the Halls","Welsh (1862)",130,
     [C5,Bb4,A4,G4,F4,G4,A4,F4,G4,A4,Bb4,G4,A4,G4,F4,E4,D4,E4,F4,G4,A4,G4,F4,E4,F4,G4,A4,Bb4,C5,A4,G4,F4],
     [0,3,0,3,1,3,0,1,3,0,2,3,0,3,1,2,1,2,1,3,0,3,1,2,1,3,0,2,0,0,3,1],
-    [4,2,2,4,2,2,2,4,2,2,2,4,2,2,2,2,2,2,2,4,2,2,2,2,2,2,2,2,4,2,2,8],
+    [3,1,2,2,3,1,2,2,2,2,2,2,3,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3,1,2,4],
     4,F4);
   var wish=carol("We Wish You a Merry Christmas","English (1500s)",140,
     [G4,C5,C5,D5,C5,B4,A4,A4,D5,D5,E5,D5,C5,B4,G4,E5,E5,F5,E5,D5,C5,A4,G4,G4,A4,D5,B4,C5],
@@ -3788,12 +3788,12 @@ const SINGALONG_PIECES=(function(){
   var amazing=pub("Amazing Grace","J. Newton (1779)",80,
     [G4,C5,E5,C5,E5,D5,C5,A4,G4,G4,C5,E5,C5,E5,D5,E5,E5,C5,A4,A4,G4,E4,G4,C5,E5,C5,E5,D5,C5],
     [3,0,2,0,2,1,0,0,3,3,0,2,0,2,1,2,2,0,0,0,3,2,3,0,2,0,2,1,0],
-    [2,2,2,2,2,2,2,2,2,2,2,2,2,2,6,2,2,2,2,2,2,2,2,2,2,2,2,2,6],
+    [2,4,3,1,2,2,2,4,4,2,4,3,1,2,2,4,4,3,1,2,2,4,2,4,3,1,2,2,6],
     4,C4);
   var auld=pub("Auld Lang Syne","R. Burns (1788)",95,
     [C4,F4,F4,F4,A4,G4,F4,G4,A4,F4,F4,A4,C5,D5,D5,D5,C5,A4,F4,F4,G4,A4,G4,F4,D4,C4],
     [0,1,1,1,0,3,1,3,0,1,1,0,0,1,1,1,0,0,1,1,3,0,3,1,1,0],
-    [2,4,2,2,2,4,2,2,2,4,2,2,2,6,2,2,2,4,2,2,2,4,2,4,2,6],
+    [2,3,1,2,3,1,2,2,3,1,2,2,2,6,2,3,1,2,3,1,2,3,1,2,2,6],
     4,F4);
   var saints=pub("When the Saints Go Marching In","Spiritual (Trad.)",120,
     [C4,E4,F4,G4,C4,E4,F4,G4,C4,E4,F4,G4,E4,C4,E4,D4,E4,E4,D4,C4,C4,E4,G4,G4,F4,E4,F4,G4,E4,C4,D4,C4],