Read wpak cfgs from one folder per archive

Files now load from mb.data/wpak/<archive>/<file>, matching MBDATA's
data/wpak layout and the client's Config/Config.wpak naming, so more
archives can sit beside Config/ later. All nine current files are in
wpak/Config/.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/engine/parsers/wpak/PowerParser.java

@@ -21,7 +21,7 @@ import java.util.HashSet;
 
 public class PowerParser {
 
-    private static final String fileName = "Powers.cfg";
+    private static final String fileName = "Config/Powers.cfg";
     private static final int headerSize = 22;
 
     // Keys the client's loader doesn't know and skips; "POWEREND=" is a typo for CURVE= on one power