authentik: fix episodic blank-screen + 30s-hang login (reliability R2)

The login screen would sometimes hang/blank for everyone for ~30s at a time.
Root-caused: the readiness probe (/-/health/ready/) queries the DB, and on a
transient PG/pgbouncer blip it 503s; with the chart-default ~30s tolerance all 3
goauthentik-server pods dropped out of the Service at once, so Traefik had no
healthy backend -> 502/503/504. Compounded by a silent drift: the repo set the
rollout strategy under `strategy:`, but the chart reads `deploymentStrategy:` —
so live ran the chart-default 25%/25% and dropped a pod out of rotation on every
roll. (Redis was removed upstream in authentik 2026.2, so sessions+cache are on
PostgreSQL and request-serving is coupled to PG — verified there is no
external-cache option to put back, so a SHORT transient is now survived but a
total CNPG outage still takes authentik down.)

Reliability package (R2, approved):
- readinessProbe.failureThreshold 3->8 (~80s) — absorbs a full CNPG failover
  reconnect without dropping the whole fleet from the Service.
- rename server+worker `strategy:` -> `deploymentStrategy:` (the real chart key)
  and set maxSurge:1/maxUnavailable:0 so a roll never dips below 3 ready.
- gunicorn AUTHENTIK_WEB__MAX_REQUESTS 1000->10000 / JITTER 50->1000 so the 9
  workers' recycles don't cluster on a DB blip.
- / and /static ingresses switch to the dedicated authentik-rate-limit (100/1000)
  from the previous commit (skip_default_rate_limit) — fixes the cold-load 429
  blank screen.

Liveness intentionally left DB-coupled-but-shallow (LiveView always returns 200,
so it can't kill a DB-blocked pod). CONN_MAX_AGE intentionally NOT set (pins the
pgbouncer pool, reverted 2026-06-10). Docs: .claude/CLAUDE.md + authentication.md
(also corrected a stale "60s persistent DB connections" note).

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

.claude/CLAUDE.md

@@ -219,7 +219,7 @@ the workflow's built-in `GITHUB_TOKEN` (`packages: write`).
 | Immich | ML on SSD (CUDA), disable ModSecurity (breaks streaming), frequent upgrades. **`immich-machine-learning` MUST run with `MACHINE_LEARNING_MODEL_TTL > 0`** (set to `600` in `stacks/immich/main.tf`, env on the `immich-machine-learning` deployment). At `0`, no model ever unloads and onnxruntime's CUDA arena (OCR's dynamic input shapes inflate it to ~10 GB) is held forever on the **time-sliced T4 it shares with llama-swap/frigate/immich-server** — which has no VRAM isolation, so immich-ml starved llama-swap (qwen3-8b) and silently broke recruiter-responder triage for ~5 h on 2026-06-02 (post-mortem `docs/post-mortems/2026-06-02-immich-ml-ttl-gpu-oom-recruiter.md`). TTL>0 lets idle models (OCR, face — AND CLIP) free VRAM. The TTL is a single GLOBAL knob (no per-model pin), so CLIP would also unload after 600s idle; the `clip-keepalive` CronJob (`*/5 * * * *`, same stack) pings the CLIP textual encoder so smart-search stays warm without pinning the ad-hoc models. **Smart search has a SECOND warmth layer in Postgres** (don't conflate it with the ML model): the ~665MB vchord `clip_index` must stay resident in PG `shared_buffers`, else an ANN probe that lands on an evicted list pays a ~1.8s cold storage read vs ~4ms warm. The `postStart` hook prewarms it ONCE at pod start and `pg_prewarm.autoprewarm` only re-warms at *startup*, so the index decays out of cache over days under job buffer-pressure (observed ~33% resident after 9d uptime → slow context search, easily misattributed to the ML model). The `clip-index-prewarm` CronJob (`*/5`, same stack) re-runs `pg_prewarm('clip_index')` to pin it hot; `immich-search-probe` (`*/5`) measures live latency + residency → Pushgateway gauges (`immich_smart_search_db_seconds`, `immich_clip_index_cached_pct`) → alerts `ImmichSmartSearchSlow`/`ImmichClipIndexColdCache`/`ImmichSearchProbeStale` + cluster-health check #46 (`check_immich_search`). immich PG role is a superuser so the CronJobs can run `pg_prewarm`/`pg_buffercache`. **Video transcoding is GPU-accelerated**: `immich-server` is pinned to GPU node1 (nodeSelector `nvidia.com/gpu.present` + NoSchedule toleration + `gpu-workload` priority) with a time-sliced `nvidia.com/gpu=1` slice — the stock immich-server image's ffmpeg already ships h264/hevc_nvenc + NVDEC. Activated via `ffmpeg.accel=nvenc` + `accelDecode=true` in the **DB** system-config (`system_metadata` table, key `system-config`, JSONB — NOT Terraform; app config is DB-managed here like oauth/smtp). Direct DB edits need a pod **recreate** to reload (config is cached at boot; only API-driven changes broadcast a reload). **Streaming bitrate is capped** to keep 4K playback smooth on the contended HDD and over remote uplinks: `ffmpeg.maxBitrate=20000k` + `preset=medium` + `transcode=bitrate` (set 2026-06-01 — was uncapped `maxBitrate=0` + `ultrafast` + `targetResolution=original`, which produced 77–264 Mbps 4K transcodes that stuttered for every client, local and remote, since even a single stream needs ~10–13.5 MB/s off the shared `sdc` spindle). 4K resolution is preserved (`targetResolution=original`); originals are NEVER modified — only the `encoded-video/` streaming copy. To re-apply transcode settings to EXISTING videos (config changes only affect new/missing ones): delete the offenders' `asset_file` rows `WHERE type='encoded_video'` (derived/regenerable — never touches originals) then run videoConversion `force=false` (admin Jobs API → "Missing"); it regenerates them to the deterministic `<assetId>.mp4` path at concurrency 1 (gentle on sdc). See `docs/runbooks/immich-transcode-bitrate.md`. If Immich is ever reinstalled fresh (not restored), re-set these keys (accel, accelDecode, **maxBitrate=20000k, preset=medium, transcode=bitrate**). Thumbnails/previews live on SSD NFS (sdb) — do NOT move to block storage (HDD sdc = slower + the contended IO domain). **Background-job concurrency is capped to protect sdc** (DB-managed system-config, `system_metadata` key `system-config`, JSONB `job.*.concurrency`; re-set on fresh install): `thumbnailGeneration=2`, `metadataExtraction=2`, `library=2` — these jobs read ORIGINALS off the HDD library. Left uncapped (were 8/4/4) a library-wide job (e.g. Duplicate Detection on 2026-06-01) fans the ML/thumbnail backfill out into a read storm that saturates sdc and starves etcd → apiserver down. `sidecar`/`smartSearch`/`faceDetection` stay at Immich defaults (small `.xmp` / SSD previews). Apply via Job Settings UI or the `system-config` API; **direct DB edits need an `immich-server` pod recreate to reload** (config cached at boot). See `docs/post-mortems/2026-05-25-immich-anca-elements-io-storm.md`. |
 | CrowdSec | Pin version, disable Metabase when not needed (CPU hog), LAPI scaled to 3, **DB on PostgreSQL** (migrated from MySQL), flush config: max_items=10000/max_age=7d/agents_autodelete=30d, DECISION_DURATION=168h in blocklist CronJob. **Enforcement is out-of-band, NOT a Traefik plugin** (the Yaegi `crowdsec-bouncer-traefik-plugin` was dead on Traefik 3.7.5 and removed): `cs-firewall-bouncer` DaemonSet drops in-kernel via nftables on direct hosts (bouncer key `firewall`, v0.0.34 binary fetched at runtime, hostNetwork+NET_ADMIN, `stacks/crowdsec/modules/crowdsec/firewall_bouncer.tf`); `crowdsec-cf-sync` CronJob blocks at the CF edge for proxied hosts (bouncer key `kvsync`, `stacks/rybbit/crowdsec_edge.tf`). Both fail open. See `docs/architecture/security.md` |
 | Frigate | GPU stall detection in liveness probe (inference speed check), high CPU |
-| Authentik | 3 server replicas + 2-replica embedded outpost (PG-backed sessions), PgBouncer in front of PostgreSQL, strip auth headers before forwarding. **`authentik.*` Helm values are INERT** (existingSecret skips chart env rendering) — tune via `server.env`/`worker.env` in `modules/authentik/values.yaml`. Single-screen login (password embedded in identification stage); all first-party OIDC apps use implicit consent (2026-06-10). `/static` ingress carve-out serves assets with immutable Cache-Control. |
+| Authentik | 3 server replicas + 2-replica embedded outpost (PG-backed sessions), PgBouncer in front of PostgreSQL, strip auth headers before forwarding. **`authentik.*` Helm values are INERT** (existingSecret skips chart env rendering) — tune via `server.env`/`worker.env` in `modules/authentik/values.yaml`. Single-screen login (password embedded in identification stage); all first-party OIDC apps use implicit consent (2026-06-10). `/static` ingress carve-out serves assets with immutable Cache-Control; `/`+`/static` use a dedicated `authentik-rate-limit` (100/1000) so the cold-load chunk burst isn't 429'd into a blank screen. **Reliability (2026-06-28): the chart key is `deploymentStrategy`, NOT `strategy`** — the old `strategy:` key was inert, so live ran the chart default 25%/25% and dropped a server pod out of rotation on every roll; now `maxSurge:1/maxUnavailable:0`. Readiness `failureThreshold:8` (~80s, was 30s): the DB-coupled `/-/health/ready/` returns 503 on a PG/pgbouncer blip, and with too-tight tolerance all 3 server pods left the Service at once → Traefik 502/504 (the episodic blank-screen + 30s-hang). gunicorn `max_requests=10000`/jitter=1000 decorrelates worker recycles from DB blips. Redis is GONE since 2026.2 (sessions+cache+channels on PostgreSQL, no external-cache option) — a short PG transient is now survived, but a TOTAL CNPG outage still takes authentik down. |
 | Kyverno | failurePolicy=Ignore to prevent blocking cluster, pin chart version |
 | MySQL Standalone | Raw `kubernetes_stateful_set_v1` pinned to `mysql:8.4.8` exactly (migrated from InnoDB Cluster 2026-04-16; **pinned to 8.4.8 on 2026-05-18** after Keel-driven `mysql:8.4` → 8.4.9 bump stalled the DD upgrade and required a full PVC-wipe + dump-restore — see `docs/runbooks/restore-mysql.md` and beads code-eme8/code-k40p). `skip-log-bin`, `innodb_flush_log_at_trx_commit=2`, `innodb_doublewrite=ON`. ConfigMap `mysql-standalone-cnf`. PVC `data-mysql-standalone-0` (5Gi initial → 30Gi via autoresizer, `proxmox-lvm-encrypted`). Service `mysql.dbaas` unchanged. Anti-affinity excludes k8s-node1. Bitnami charts deprecated (Broadcom Aug 2025) — use official images. |
 | phpIPAM | IPAM — no active scanning. `pfsense-import` CronJob (hourly) pulls Kea leases + ARP via SSH. `dns-sync` CronJob (15min) bidirectional sync with Technitium. Kea DDNS on pfSense handles all 3 subnets. API app `claude` (ssl_token). |