feat: cancel running instances as CANCELLED without initiator checks

Co-authored-by: Cursor <cursoragent@cursor.com>

ordo-api/src/main/java/com/jetlumen/ordo/api/OrdoEngine.java

@@ -38,6 +38,11 @@ public interface OrdoEngine {
         return withdraw(instanceId, actor, null);
     }
     ProcessInstance withdraw(String instanceId, String actor, String comment);
+
+    default ProcessInstance cancel(String instanceId, String actor) {
+        return cancel(instanceId, actor, null);
+    }
+    ProcessInstance cancel(String instanceId, String actor, String comment);
     Optional<ProcessInstance> findInstance(String instanceId);
     Optional<ApprovalTask> findTask(String taskId);
     List<ApprovalTask> findTasks(String instanceId);

ordo-api/src/main/java/com/jetlumen/ordo/api/ProcessEventType.java

@@ -12,6 +12,7 @@ public enum ProcessEventType {
     INSTANCE_APPROVED,
     INSTANCE_REJECTED,
     INSTANCE_WITHDRAWN,
+    INSTANCE_CANCELLED,
     ACTION_SUCCEEDED,
     ACTION_FAILED
 }

ordo-api/src/main/java/com/jetlumen/ordo/api/ProcessStatus.java

@@ -1,5 +1,5 @@
 package com.jetlumen.ordo.api;
 
 public enum ProcessStatus {
-    RUNNING, APPROVED, REJECTED, WITHDRAWN
+    RUNNING, APPROVED, REJECTED, WITHDRAWN, CANCELLED
 }