Invalid regex for prefix throws uncaught exception

[tpwalke2]

Malformed REGEX marker-group prefix throws uncaught, blocking sign processing broadly
src/main/java/com/tpwalke2/bluemapsignmarkers/core/signs/SignLinesParser.java:80-90
line.matches(markerGroup.prefix()) / line.replaceAll(markerGroup.prefix(), "") use the raw config string as a
regex with zero validation anywhere in the chain — ConfigProvider never test-compiles it. A single typo'd regex
throws PatternSyntaxException the first time matching reaches that group, and because groups are tried in
configured order until one matches, a bad regex placed early can throw for essentially every sign the server
processes, not just ones meant for that group. Propagates uncaught out of SignBlockEntityInject's @Inject
callback and BlueMapSignMarkersMod.onBlockEntityLoad.