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/readme.md

@@ -0,0 +1,33 @@
+# Servers
+
+### Horst
+
+- ip: 10.0.0.5
+- os: CentOS release 6.9 (Final)
+- services:
+    - apache tcp/80
+    - postgres tcp/5432
+    - samba (not really in use)
+    - cronjobs
+        - /srv/bin/pg_psmf_dump.sh
+        - /srv/bin/psmf-prepare-tables.sh 2023 2027
+        - /srv/bin/psmf-api-sync.sh
+
+- specials:
+    -   some binaries/libraries relevant to PDF printing from the app WKHTML        
+
+```bash
+# crontab content
+00 11,15,19,22 * * * root /srv/bin/pg_psmf_dump.sh
+55 10,14,18,21 * * * root /srv/bin/psmf-prepare-tables.sh 2023 2027
+05 11,15,19,22 * * * root /srv/bin/psmf-api-sync.sh
+```
+
+#### Problems
+
+- operating system is already that old, that there is not reasonable and safe upgrade path to something current
+
+
+### Horst-2
+
+- ip: 10.0.0.6