docs: fix pre-existing broken links surfaced by docs-lint

Problem: docs-lint (added in the wiki-hq reorg) surfaced 126 broken relative
links that predated this session — a container rename, incident/plan docs
that moved into archive/done subfolders without their inbound links being
updated, and a handful of relative-depth bugs in files nested under
containers/archive/ and plans/done/.

Fixes applied, by category:
- 124-authentik.md -> 106-auth-outpost.md (container was renamed; ~40 refs).
- investigations/{2026-04-21-hubris-crash-loop,2026-05-31-authentik-vps-migration}.md
  -> archive/ prefix (both moved to investigations/archive/ previously).
- plans/{2026-06-01-slate-ax-to-sodola-migration,2026-06-04_130000-deprecate-claudio-bot,
  2026-06-25-yuvomi-deployment}.md -> plans/done/ prefix.
- Depth bugs in files nested one level deeper than their siblings assumed
  (investigations/archive/*, knowledge/wiki/containers/archive/*,
  plans/done/*) — corrected relative-path depth.
- Destroyed containers with no surviving page (126-plato) delinked to the
  containers/index.md archaeology row instead of a 404.
- ludo-mini.yaml -> strong.yaml (host was renamed, same physical machine).
- netbird-vps.md (no narrative page exists) -> netbird-vps.yaml (substrate
  record, matching the existing convention for hosts without a wiki page).
- runbook-dpkg-interrupted.md refs -> .agents/skills/runbook-dpkg-interrupted/SKILL.md
  (missed in the phase-4 runbook move because the referencing files used a
  bare filename, not a runbooks/ prefix).
- One dangling forward-reference to a never-written investigation delinked
  to the actual incident record it was describing.

Left alone: two links in knowledge/wiki/containers/101-jellyfin.md into
devops/homelab-authentik-admin/ — an intentional reference to a sibling repo,
not present in this checkout.

Verification: broken-link count 126 -> 2 (real remainder is the cross-repo
reference above); gen-topology.py --check still exit 0; build_host_files.py
still idempotent; all inventory.yaml doc_page targets still resolve.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

knowledge/wiki/containers/114-nextcloud.md

@@ -11,7 +11,7 @@ Personal cloud / file collaboration. Source-of-truth for the photo libraries sur
 - **Public hostname:** [`cloud.hubris.network`](../infrastructure/dns.md) → [caddy](121-caddy.md)
 
 ## Auth
-Native OIDC via `user_oidc` app. **Username override pattern**: Authentik user `dtoro` maps to local Nextcloud user `admin` via the `nc_uid` custom-claim scope. Configured via `occ user_oidc:provider <name> --mapping-uid=nc_uid` and `--scope="openid profile email <app>-uid"`. See [Authentik](124-authentik.md#per-app-username-override-pattern-authentik) for the full pattern.
+Native OIDC via `user_oidc` app. **Username override pattern**: Authentik user `dtoro` maps to local Nextcloud user `admin` via the `nc_uid` custom-claim scope. Configured via `occ user_oidc:provider <name> --mapping-uid=nc_uid` and `--scope="openid profile email <app>-uid"`. See [Authentik](106-auth-outpost.md#per-app-username-override-pattern-authentik) for the full pattern.
 
 Redirect URI: `/index.php/apps/user_oidc/code` (NOT `/apps/...` — pretty URLs aren't on).
 
@@ -74,7 +74,7 @@ Apply with `systemctl restart mariadb` (not reload — `innodb_log_file_size` ne
 
 ## Related
 - [mulita (120)](120-mule-images.md) — reads NC user trees + writes back via WebDAV
-- [Authentik (124)](124-authentik.md)
+- [Authentik (124)](106-auth-outpost.md)
 - [Caddy (121)](121-caddy.md)
 - [DNS](../infrastructure/dns.md)
 - [Mesh migration (DNS overrides explained)](../infrastructure/mesh.md)