ensure tag mode can't work with workflow dispatch and schedule tasks

src/modes/tag/index.ts

@@ -53,6 +53,17 @@ export const tagMode: Mode = {
   }: ModeOptions): Promise<ModeResult> {
     // Tag mode handles entity-based events (issues, PRs, comments)
 
+    // Validate this mode can handle the event
+    if (
+      context.eventName === "workflow_dispatch" ||
+      context.eventName === "schedule"
+    ) {
+      throw new Error(
+        `Tag mode cannot handle ${context.eventName} events. ` +
+          `Use 'agent' mode for automation events.`,
+      );
+    }
+
     // Check if actor is human
     await checkHumanActor(octokit.rest, context);