feat: added sync group table and models

migrations/2025-02-23-095541_initial/up.sql

@@ -24,6 +24,9 @@ create table devices (
     user_id bigint not null
         references users (id)
         on delete cascade,
+    sync_group_id bigint
+        references sync_group (id)
+        on delete set null,
 
     caption text not null,
     type text not null,
@@ -31,6 +34,10 @@ create table devices (
     unique (user_id, device_id)
 );
 
+create table sync_groups (
+    id integer primary key not null
+);
+
 create table device_subscriptions (
     id integer primary key not null,