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>

vms/docker-dev-22/psmf-data-sync/.env

@@ -0,0 +1,20 @@
+# Image (built by .gitea/workflows/build.yaml)
+# IMAGE_REPO is the Gitea repo path, e.g. "jan/psmf-data-sync"
+IMAGE_REPO=gitea.home.hrajfrisbee.cz/psmf/psmf-data-syncer
+IMAGE_TAG=0.2
+
+# Host port to publish the syncer on (container listens on 8002 internally)
+HOST_PORT=8003
+
+# External Postgres the syncer restores into
+DB_HOST=192.168.123.23
+DB_PORT=5432
+DB_NAME=psmf-dev
+DB_USER=psmf-dev
+DB_PASSWORD=** masked even when it is so secret **
+
+# Which Redis DB index to use (0-15)
+REDIS_DB=0
+
+# info | debug
+LOG_LEVEL=debug