A bit of DB model cleanup (#5016)

Content.Server.Database/add-migration.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+if [ -z "$1" ] ; then
+    echo "Must specify migration name"
+    exit 1
+fi
+
+dotnet ef migrations add --context SqliteServerDbContext -o Migrations/Sqlite "$1"
+dotnet ef migrations add --context PostgresServerDbContext -o Migrations/Postgres "$1"