client: add ability to inject custom cs2 scripts

runelite-api/src/main/java/net/runelite/api/Client.java

@@ -1894,6 +1894,14 @@ public interface Client extends OAuthApi, GameEngine
 	 */
 	void setBlacklistDeadNpcs(Set<Integer> blacklist);
 
+	/**
+	 * Adds a custom clientscript to the list of available clientscripts.
+	 *
+	 * @param script compiled clientscript code
+	 * @return the id of the newly-added script
+	 */
+	int addClientScript(byte[] script);
+
 	/**
 	 * Gets an array of tile collision data.
 	 * <p>

runelite-api/src/main/java/net/runelite/api/overlay/OverlayIndex.java

@@ -29,11 +29,13 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.HashSet;
 import java.util.Set;
+import lombok.Getter;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
 public class OverlayIndex
 {
+	@Getter
 	private static final Set<Integer> overlays = new HashSet<>();
 
 	static