Bump pinned images to latest: authentik 2026.8.3, tautulli ls245, calibre-web ls402, plex 1.43.4

- authentik 2026.8.0 -> 2026.8.3 (server, worker, outpost quadlets)
- tautulli v2.18.1-ls242 -> v2.18.1-ls245
- calibre-web 0.6.27-ls397 -> 0.6.27-ls402
- plex 1.43.3.10896-ls322 -> 1.43.4.10903-ls325
- seerr already at v3.4.1 (latest, no bump)
- sync docs + the dead compose.yaml plex entry

anubis is already at the latest stable (v1.27.0); only pre-releases exist
beyond it, so no stable bump. Local-build images (caddy, alloy, loki,
comfyui, hermes) are refreshed by forced --no-cache rebuilds, not pins.

serverAppConfigs-docs/index.md

@@ -46,7 +46,7 @@ covers both workloads).
 - [[Calibre-Web]] — e-book web frontend
 - [[Plex]] — media server on Dankserver (lscr.io/linuxserver/plex container via
   quadlet; CPU decode only — no GPU passthrough)
-- [[Tautulli]] — Plex statistics and notifications (v2.18.1-ls242, quadlet unit)
+- [[Tautulli]] — Plex statistics and notifications (v2.18.1-ls245, quadlet unit)
 - [[mariadb]] — RomM database backend
 - [[redis]] — RomM cache/queue backend