feat(portal): add SSR operations and exclusive groups

packages/database/drizzle/0003_smiling_silver_samurai.sql

@@ -0,0 +1,11 @@
+DROP INDEX "user_group_memberships_user_group_uidx";--> statement-breakpoint
+DELETE FROM "user_group_memberships"
+WHERE ctid IN (
+  SELECT ctid
+  FROM (
+    SELECT ctid, row_number() OVER (PARTITION BY "user_id" ORDER BY "created_at" DESC, "group_id") AS assignment_rank
+    FROM "user_group_memberships"
+  ) ranked_assignments
+  WHERE assignment_rank > 1
+);--> statement-breakpoint
+CREATE UNIQUE INDEX "user_group_memberships_user_uidx" ON "user_group_memberships" USING btree ("user_id");