feat: implement auth system, passkeys, and user management

Add PostgreSQL and Redis integration for users and sessions
Implement password and WebAuthn passkey login flows
Add Docker stack, super-admin seeding, and protected routes

server/utils/postgres.ts

@@ -0,0 +1,18 @@
+import postgres from 'postgres'
+
+let sqlClient: postgres.Sql | null = null
+
+export function getSqlClient() {
+  if (!sqlClient) {
+    const config = useRuntimeConfig()
+
+    sqlClient = postgres(
+      config.databaseUrl || 'postgresql://postgres:postgres@127.0.0.1:5432/dinner_ticket_system',
+      {
+        max: 10
+      }
+    )
+  }
+
+  return sqlClient
+}