Add draft catalog lane for railiance backup offsite credentials.

Points at CCR-2026-0004 OpenBao path; playbook documents bao login and
fetch shapes for railiance-backup and forgejo-backup tooling.

wiki/playbooks/railiance-backup-offsite-lane.md

@@ -0,0 +1,59 @@
+# Railiance Offsite Backup Lane
+
+Date: 2026-07-07  
+Catalog: `railiance-backup-offsite-lane` (status `draft`, `resolvable: false` until verified)  
+Owner: `railiance-platform` (CCR-2026-0004)
+
+Nextcloud WebDAV upload token and URL for age-encrypted offsite backups (Option A).
+Used by `railiance-backup` (workstation) and `forgejo-backup` (platform).
+
+---
+
+## OpenBao pointers
+
+| Field | Value |
+| --- | --- |
+| Mount | `platform` |
+| Path | `platform/workloads/railiance/backup/offsite-lane` |
+| Fields | `NC_WEBDAV_TOKEN`, `NC_WEBDAV_URL`, `AGE_PRIVATE_KEY` |
+| Policy | `workload-kv-read-railiance-backup-offsite-lane` |
+| OIDC role | `railiance-backup-workload-kv-read` (`groups=net-kingdom-admins`) |
+
+---
+
+## Worker checklist
+
+1. **Login** (caller identity — ops-warden adds no credential):
+
+   ```bash
+   bao login -method=oidc -path=netkingdom role=railiance-backup-workload-kv-read
+   ```
+
+2. **Export for a backup run** (value streams to your shell — never paste into chat):
+
+   ```bash
+   export RAILIANCE_BACKUP_NC_TOKEN=$(
+     bao kv get -field=NC_WEBDAV_TOKEN platform/workloads/railiance/backup/offsite-lane
+   )
+   export RAILIANCE_BACKUP_NC_WEBDAV_URL=$(
+     bao kv get -field=NC_WEBDAV_URL platform/workloads/railiance/backup/offsite-lane
+   )
+   ```
+
+3. **Or proxy via warden access** (after catalog promotion):
+
+   ```bash
+   warden access railiance-backup-offsite-lane --no-policy --fetch --field NC_WEBDAV_TOKEN
+   ```
+
+4. **Run backup**:
+
+   ```bash
+   # workstation custodian DB + config
+   bin/railiance backup
+
+   # Forgejo production (from railiance-platform checkout)
+   tools/cmd/forgejo-backup
+   ```
+
+`AGE_PRIVATE_KEY` in the same path is recovery escrow — fetch only for restore drills.