Add Runbook Automator dashboard - automated incident response playbooks

New feature: Interactive Runbook Automator (dashboard/runbooks.html)
- Create, manage, and simulate automated incident response runbooks
- Define trigger conditions (metric + threshold + time window)
- Multi-step workflows with 4 step types: action, check, gate, notify
- Approval gates pause execution for human-in-the-loop review
- Live simulation with step-by-step execution and progress bar
- Execution history with success/failure/partial tracking
- 5 pre-built runbooks: error rate, cost overrun, latency, anomaly, SLA breach
- Search, enable/disable, delete runbooks
- Overview stats: total runbooks, active count, executions, success rate
- Full dark/light theme support, localStorage persistence
- Added nav link from main dashboard

Usage: Click 'Runbooks' in the dashboard header navigation

Author: sauravbhattacharya001

dashboard/index.html

@@ -28,6 +28,7 @@ <h1 class="logo">🔍 AgentLens</h1>
         <a href="alerts.html" class="btn btn-alert-header" style="text-decoration:none">🚨 Alert Rules</a>
         <a href="profiler.html" class="btn btn-alert-header" style="text-decoration:none">🧬 Profiler</a>
         <a href="correlator.html" class="btn btn-alert-header" style="text-decoration:none">🔗 Correlator</a>
+        <a href="runbooks.html" class="btn btn-alert-header" style="text-decoration:none">📋 Runbooks</a>
         <button class="btn btn-alert-header" onclick="openAlertsModal()" id="alertsBtn">
           🔔 Alerts <span class="alert-badge" id="alertBadge" style="display:none">0</span>
         </button>