fix: backup LUKS rsync tolerance, stale mapping cleanup, tier-4-aux quota bump

- daily-backup: handle rsync exit 23 (partial transfer) as OK for LUKS
  noload mounts — in-flight writes have corrupt metadata from skipped
  journal replay, but core data is intact
- daily-backup: clean up stale LUKS dm mappings from previous crashed
  runs before attempting to open
- daily-backup: capture rsync exit code safely with set -e (|| pattern)
- kyverno: bump tier-4-aux requests.memory 2Gi→3Gi (servarr was at 83%)
- actualbudget: patched custom quota 5Gi→6Gi (was at 82%)

Verified: backup now completes status=0 (96 PVCs OK, 0 failed)

[ci skip]

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

stacks/kyverno/modules/kyverno/resource-governance.tf

@@ -711,7 +711,7 @@ resource "kubernetes_manifest" "generate_resourcequota_by_tier" {
               spec = {
                 hard = {
                   "requests.cpu"    = "2"
-                  "requests.memory" = "2Gi"
+                  "requests.memory" = "3Gi"
                   "limits.memory"   = "16Gi"
                   pods              = "20"
                 }