more ambitious ISABELLE_JAVA_SYSTEM_OPTIONS, following 1a4be2516f50;
enforce rebuild of Isabelle/ML and Isabelle/Scala;

--- a/etc/settings	Thu Aug 07 12:35:37 2025 +0200
+++ b/etc/settings	Thu Aug 07 13:02:14 2025 +0200
@@ -12,7 +12,7 @@
 ### Isabelle/Scala
 ###
 
-ISABELLE_JAVA_SYSTEM_OPTIONS="-server -Dfile.encoding=UTF-8 -Disabelle.threads=0 -XX:+UseZGC -XX:+ZGenerational"
+ISABELLE_JAVA_SYSTEM_OPTIONS="-server -Dfile.encoding=UTF-8 -Disabelle.threads=0 -XX:+UseZGC -XX:+ZGenerational -XX:+UseStringDeduplication"
 
 ISABELLE_TOOL_JAVA_OPTIONS="-Djava.awt.headless=true -Xms512m -Xmx4g -Xss16m"
 

--- a/src/Pure/ROOT.ML	Thu Aug 07 12:35:37 2025 +0200
+++ b/src/Pure/ROOT.ML	Thu Aug 07 13:02:14 2025 +0200
@@ -1,6 +1,6 @@
 (*  Title:      Pure/ROOT.ML
     Author:     Makarius
-    UUID:       2dddcab9-800b-4158-b53a-f20f73aa7663
+    UUID:       42ae3ec9-f60f-42f1-8127-8d951cdb7073
 
 Main entry point for the Isabelle/Pure bootstrap process.
 

--- a/src/Pure/ROOT.scala	Thu Aug 07 12:35:37 2025 +0200
+++ b/src/Pure/ROOT.scala	Thu Aug 07 13:02:14 2025 +0200
@@ -1,6 +1,6 @@
 /*  Title:      Pure/ROOT.scala
     Author:     Makarius
-    UUID:       619a7a37-9241-410f-82a1-be35d8c9e937
+    UUID:       42ae3ec9-f60f-42f1-8127-8d951cdb7073
 
 Root of isabelle package.
 */