fix: add safety check to metrics cleanup to prevent accidental deletion

Add validation to ensure patterns array is not empty before attempting
to clean up metrics streams. This prevents accidental deletion of all
metrics streams if the method is called without proper patterns.

Safety improvement for cleanupMetricsStreams() method.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

tests/ui-testing/pages/apiCleanup.js

@@ -1039,6 +1039,12 @@ class APICleanup {
             protectedStreams
         });
 
+        // Safety check: If no patterns provided, don't delete anything
+        if (patterns.length === 0) {
+            testLogger.info('No patterns provided for metrics cleanup - skipping');
+            return;
+        }
+
         try {
             // Fetch all metrics streams
             const streams = await this.fetchMetricsStreams();