docs(changelog): state the voice hint saving without main's size

Co-Authored-By: Claude Opus 5.5 <[email protected]>

changelog.d/1462-voice-alias-hint-budget.md

@@ -1,5 +1,5 @@
 - Leave layer aliases the layer id already spells, such as "dams" for
-  `local-dams`, out of the voice layer hint. The Realtime prompt drops from
-  52,000 to 51,695 characters, leaving room under the 52,000 gate for new
+  `local-dams`, out of the voice layer hint. The Realtime prompt is 305
+  characters shorter, leaving room under the 52,000 gate for new
   voice-toggleable layers; every alias is still accepted (quanticsoul4772,
   #1462).