servers/psmf: add psmf server docs, nginx/tailscale config, and data-sync

Document the psmf host (DNS, second tailscale netns instance, nginx
vhosts, migration plan) and add the docker-dev-22 psmf-data-sync
service plus the storage-23 pg_hba.conf entry it needs.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

servers/psmf/files/ts2-netns.service

@@ -0,0 +1,17 @@
+# /etc/systemd/system/ts2-netns.service
+
+[Unit]
+Description=ts2 netns + veth + NAT
+After=network-online.target
+Wants=network-online.target
+# tie tailscaled lifecycle to this
+Before=tailscaled-ts2.service
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/local/sbin/ts2-netns-up
+ExecStop=/usr/local/sbin/ts2-netns-down
+
+[Install]
+WantedBy=multi-user.target