Disable XML entity expansion limit in saxon.sh

DTBook files reference DTD character entities extensively; JDK 11+
defaults to a limit of 2500 expansions which real documents exceed.
Setting jdk.xml.entityExpansionLimit=0 removes the limit. This is
safe as we process trusted internal documents only.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: egli

saxon.sh

@@ -22,4 +22,4 @@
 DIR=`dirname $0`
 CP=$(find "$DIR/lib" -name '*.jar' | tr '\n' ':')
 
-java -cp $CP ch.sbs.dtbook2sbsform.SbsTransform "$@"
+java -Djdk.xml.entityExpansionLimit=0 -cp $CP ch.sbs.dtbook2sbsform.SbsTransform "$@"