CHANGE: added db initialization script

DB/initdb/02_create_user.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+set -e  # Exit on error
+
+echo "Creating PostgreSQL user and setting permissions..."
+
+psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" <<-EOSQL
+    CREATE USER $POSTGRES_API_USER WITH ENCRYPTED PASSWORD '$POSTGRES_API_PASSWORD';
+    GRANT CONNECT ON DATABASE $POSTGRES_DB TO $POSTGRES_API_USER;
+    GRANT USAGE ON SCHEMA public TO $POSTGRES_API_USER;
+    GRANT SELECT, INSERT, UPDATE ON ALL TABLES IN SCHEMA public TO $POSTGRES_API_USER;
+EOSQL
+
+echo "User creation and permissions setup complete!"