Add sanoid Ansible role for ZFS snapshots and replication

Replaces manually deployed config files with a fully idempotent role:
installs sanoid, templates sanoid.conf and syncoid service/timer from
variables, enables both systemd timers. Removes static proxmox/sanoid.*
files. README rebuild section updated accordingly.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

proxmox/sanoid.conf

@@ -1,28 +0,0 @@
-# VM disks on SSD pool — snapshot daily/weekly
-[rpool/data]
-    use_template = vms
-    recursive = yes
-
-# Proxmox OS root — lighter schedule, mainly for recovery
-[rpool/ROOT]
-    use_template = system
-    recursive = yes
-
-#############################
-[template_vms]
-    daily = 7
-    weekly = 4
-    monthly = 0
-    hourly = 0
-    frequently = 0
-    autosnap = yes
-    autoprune = yes
-
-[template_system]
-    daily = 3
-    weekly = 2
-    monthly = 0
-    hourly = 0
-    frequently = 0
-    autosnap = yes
-    autoprune = yes

proxmox/syncoid.service

@@ -1,8 +0,0 @@
-[Unit]
-Description=Syncoid ZFS replication to HDD
-After=zfs.target
-
-[Service]
-Type=oneshot
-ExecStart=/usr/sbin/syncoid --recursive --no-privilege-elevation rpool/data hdd/backups/rpool-data
-ExecStart=/usr/sbin/syncoid --no-privilege-elevation rpool/ROOT/pve-1 hdd/backups/pve-root

proxmox/syncoid.timer

@@ -1,11 +0,0 @@
-[Unit]
-Description=Daily ZFS replication to HDD
-After=sanoid.timer
-
-[Timer]
-OnCalendar=*-*-* 02:00:00
-RandomizedDelaySec=10min
-Persistent=true
-
-[Install]
-WantedBy=timers.target