feat(dynamic): remap command injection sink cap to CODE_EXEC, update corpus markers to NYX_PWN_791_CMDI, and enhance spec derivation strategies for wider coverage and consistency

tests/dynamic_fixtures/class_method/java_recursive_deps/Benign.java

@@ -2,7 +2,7 @@
 public class Benign {
     public static class ShellRunner {
         public String run(String command) {
-            return command.replace("NYX_PWN_CMDI", "");
+            return command.replace("NYX_PWN", "");
         }
     }