Migration: consolidate Echo6 docs to cortex with full infrastructure cleanup sync

- Documents recent infrastructure cleanup (8 CTs destroyed, 35 DNS records removed, Headscale cleanup)
- Adds 24 new runbooks covering Authentik, PeerTube, Meshtastic, RECON, Proxmox, Mailcow, Internet Archive, GPU routing
- Adds project documentation for headscale, vaultwarden, peertube, matrix, mmud, advbbs, arr stack
- Updates services.md, environment.md, caddy.md, authentik.md to match live infrastructure
- Removes 4 deprecated runbook duplicates (canonical versions live in projects/)
- Adds .gitignore for binary archives and editor temp files

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/services/usenet.md

@@ -0,0 +1,53 @@
+# Usenet Configuration
+
+> **Credentials:** All passwords and API keys stored in `/home/zvx/projects/.ref/credentials`
+
+## Infrastructure
+
+| Component | Location | IP | Port | Access |
+|-----------|----------|-----|------|--------|
+| SABnzbd | arr VM (media VM 105) | 192.168.1.160 | 8080 | Internal only (LAN/Tailscale) |
+
+## Usenet Providers
+
+### Giganews
+
+| Field | Value |
+|-------|-------|
+| Host | news.giganews.com |
+| Port | 563 |
+| SSL | Yes |
+| Username | gn1369344 |
+| Password | (see .ref/credentials) |
+| Connections | 100 |
+
+### EasyUsenet
+
+| Field | Value |
+|-------|-------|
+| Host | reader.easyusenet.nl |
+| Port | 563 |
+| SSL | Yes |
+| Username | esy_6926b8b819b97 |
+| Password | (see .ref/credentials) |
+| Connections | 100 |
+| Speed | 2000 Mbit/s |
+| Retention | 3700+ days |
+| Alt Ports (SSL) | 443 |
+| Alt Ports (non-SSL) | 119, 80 |
+
+## Usenet Indexers
+
+### NZBgeek
+
+| Field | Value |
+|-------|-------|
+| URL | https://api.nzbgeek.info |
+| API Key | (see .ref/credentials) |
+
+### NinjaCentral
+
+| Field | Value |
+|-------|-------|
+| URL | https://ninjacentral.co.za |
+| API Key | (see .ref/credentials) |