Add database schema and Kysely packages

- Create initial database migration with full auth schema:
  - users, sessions, passkeys, devices tables
  - orgs, org_members, org_sites, org_invites tables
  - email_verifications, password_resets, login_requests tables
  - Indexes for common lookups and cleanup jobs
- Add @reviq/db-schema package with kysely-codegen
- Add @reviq/db package with Kysely client

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/db-schema/src/index.ts

@@ -0,0 +1,10 @@
+/**
+ * Database schema types generated from PostgreSQL schema
+ *
+ * @module @reviq/db-schema
+ */
+
+export * from "./types.js";
+
+// Re-export DB as Database for convenience
+export type { DB as Database } from "./types.js";