fix: use toWizardToolErrorContent for batch validation error in confirm_event_plan

Author: cursoragent

src/lib/wizard-tools.ts

@@ -1947,14 +1947,13 @@ For codebases with >50 events the wizard runs the WRITE phase in chunks of ~25 e
       });
       if (batchError) {
         logToFile(`confirm_event_plan: rejected batch metadata: ${batchError}`);
-        return {
-          content: [
-            {
-              type: 'text' as const,
-              text: `error: invalid batch metadata — ${batchError}. Re-call without batch fields to fall back to single-batch behavior, or fix the metadata and retry.`,
-            },
-          ],
-        };
+        return toWizardToolErrorContent({
+          error: `invalid batch metadata — ${batchError}`,
+          guidance:
+            'Re-call confirm_event_plan without batch fields to fall back to single-batch behavior, or fix the metadata and retry.',
+          suggestedTool: 'mcp__wizard-tools__confirm_event_plan',
+          context: `batchIndex: ${args.batchIndex}; totalBatches: ${args.totalBatches}; chunkSize: ${args.chunkSize}; eventCount: ${args.events.length}`,
+        });
       }
       // Soft-gate the name format. Agents historically saw conflicting
       // guidance (commandments said Title Case, the tool schema said