chore: bring immich back up, keep cephfs-metadata degraded until the end

jupiter is converted and its OSD rebuilt, so the capacity constraint that took
immich down is gone with all three nodes back.

cephfs-metadata deliberately stays at size 2 / min_size 1. It has to be
degraded again for saturn and then neptune, and each transition re-replicates
the pool, so toggling it per node buys nothing but churn. Its comment said to
restore it once k8s-1 was back, which is now misleading about the plan; it
restores after the last conversion instead.

The immich comments lose their jupiter-specific framing — taking both
Deployments down is a pre-flight step for any single-node maintenance now, and
the runbook carries it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

kubernetes/apps/immich/machine-learning.yaml

@@ -6,17 +6,14 @@ metadata:
   labels:
     app.kubernetes.io/name: immich-machine-learning
 spec:
-  # TEMPORARY — RESTORE TO 1 ONCE k8s-1 HAS REJOINED.
-  #
-  # Down for the jupiter bare-metal conversion. With one of three nodes out,
-  # the remaining pair have no room: cluster CPU requests exceed two nodes'
-  # capacity, and k8s-3 runs ~5.8 GiB above the kubelet's eviction threshold,
-  # so every pod that does not need to be running is one less thing competing
-  # for both. This one is the best candidate: 500m reserved against a measured
-  # 2m idle draw, and inference bursts hard enough that lowering the request
-  # instead would be the wrong trade. Photo processing pauses; nothing else
-  # depends on it.
-  replicas: 0
+  # Scale this and immich-server to 0 for the duration of any single-node
+  # maintenance — cluster CPU requests exceed what two nodes can hold, and this
+  # pair frees ~1000m against a shortfall of roughly 200m. Stopping them is the
+  # right lever rather than lowering their requests: 500m reserved against a
+  # 2m idle draw looks like waste, but inference bursts hard and the request is
+  # honest about what it needs when someone uploads photos.
+  # See RUNBOOK-baremetal-conversion.md.
+  replicas: 1
   strategy:
     type: RollingUpdate
   selector:

kubernetes/apps/immich/server.yaml

@@ -36,11 +36,10 @@ metadata:
   labels:
     app.kubernetes.io/name: immich-server
 spec:
-  # TEMPORARY — RESTORE TO 1 ONCE k8s-1 HAS REJOINED. See the note on
-  # immich-machine-learning; immich is offline for the jupiter conversion.
-  # Its Postgres cluster is deliberately left running, so nothing needs
-  # restoring beyond these two replica counts.
-  replicas: 0
+  # Scaled to 0 alongside immich-machine-learning during single-node
+  # maintenance; see the note there. The CNPG Postgres cluster stays running,
+  # so recovery is just these two replica counts.
+  replicas: 1
   strategy:
     type: Recreate
   selector:

kubernetes/infrastructure/rook-ceph-cluster/storageclass.yaml

@@ -87,7 +87,10 @@ metadata:
   name: cephfs
   namespace: rook-ceph
 spec:
-  # TEMPORARY — REVERT TO size 3 / no min_size OVERRIDE ONCE k8s-1 IS BACK.
+  # TEMPORARY — RESTORE TO size 3 / no min_size OVERRIDE ONCE SATURN AND
+  # NEPTUNE HAVE BOTH BEEN CONVERTED TO BARE METAL. It stays at 2/1 across all
+  # three conversions rather than being toggled per node: each change
+  # re-replicates the pool, and the window reopens with the next node anyway.
   #
   # The standing trade for this pool is size 3: it holds ~253 MiB against the
   # data pool's 280 GiB, so it contributes nothing measurable to drive wear —
@@ -96,13 +99,14 @@ spec:
   # quarter of a gigabyte to keep that intact is the right trade in steady
   # state.
   #
-  # It does not hold while one of three hosts is out for the jupiter bare-metal
-  # conversion. size 3 on two remaining hosts leaves every PG undersized at two
-  # copies with min_size 2, so a single further OSD loss drops the pool below
-  # min_size and blocks IO on every CephFS mount cluster-wide. At 2/1 the same
-  # two copies are active+clean instead, and a further loss degrades rather
-  # than blocks — availability bought at the cost of accepting writes onto a
-  # single copy while degraded.
+  # It does not hold while one of three hosts is out. size 3 on two remaining
+  # hosts leaves every PG undersized at two copies with min_size 2, so a single
+  # further OSD loss drops the pool below min_size and blocks IO on every
+  # CephFS mount cluster-wide. At 2/1 the same two copies are active+clean
+  # instead, and a further loss degrades rather than blocks — availability
+  # bought at the cost of accepting writes onto a single copy while degraded.
+  #
+  # See RUNBOOK-baremetal-conversion.md.
   metadataPool:
     replicated:
       size: 2