merge: resolve conflicts, add SELinux AVC chart article; update indexes to 53

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

SUMMARY.md

@@ -22,6 +22,8 @@
     * [Tuning Netdata Web Log Alerts](02-selfhosting/monitoring/tuning-netdata-web-log-alerts.md)
     * [Tuning Netdata Docker Health Alarms](02-selfhosting/monitoring/netdata-docker-health-alarm-tuning.md)
     * [Deploying Netdata to a New Server](02-selfhosting/monitoring/netdata-new-server-setup.md)
+    * [Netdata SELinux AVC Denial Monitoring](02-selfhosting/monitoring/netdata-selinux-avc-chart.md)
+    * [Netdata n8n Enriched Alert Emails](02-selfhosting/monitoring/netdata-n8n-enriched-alerts.md)
     * [Linux Server Hardening Checklist](02-selfhosting/security/linux-server-hardening-checklist.md)
     * [Standardizing unattended-upgrades with Ansible](02-selfhosting/security/ansible-unattended-upgrades-fleet.md)
 * [Open Source & Alternatives](03-opensource/index.md)
@@ -56,4 +58,3 @@
     * [Ollama Drops Off Tailscale When Mac Sleeps](05-troubleshooting/ollama-macos-sleep-tailscale-disconnect.md)
     * [ClamAV CPU Spike: Safe Scheduling with nice/ionice](05-troubleshooting/security/clamscan-cpu-spike-nice-ionice.md)
     * [Ansible: Vault Password File Not Found](05-troubleshooting/ansible-vault-password-file-missing.md)
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