feat(topology): create database extensions and schema

Co-Authored-By: Claude <noreply@anthropic.com>

topology_api/migrations/001_extensions.sql

@@ -0,0 +1,8 @@
+-- topology_api/migrations/001_extensions.sql
+-- Create schema and required PostgreSQL extensions
+
+CREATE SCHEMA IF NOT EXISTS topology;
+
+CREATE EXTENSION IF NOT EXISTS pgcrypto WITH SCHEMA topology;
+CREATE EXTENSION IF NOT EXISTS citext WITH SCHEMA topology;
+CREATE EXTENSION IF NOT EXISTS btree_gist WITH SCHEMA topology;