feat: implement user management features including creation, updating, and deletion of users

- Added user management routes and logic in `+page.server.ts` for creating, updating, resetting passwords, and deleting users.
- Created a user management interface in `+page.svelte` with dialogs for user actions.
- Integrated password validation and hashing using `@node-rs/argon2`.
- Updated database schema to include a `user` table with necessary fields.
- Seeded a default admin user during database migration if no users exist.
- Added necessary dependencies in `package.json`.

server/package.json

@@ -7,6 +7,7 @@
     "start": "bun run src/index.ts"
   },
   "dependencies": {
+    "@node-rs/argon2": "^2.0.2",
     "elysia": "^1.2.0",
     "mysql2": "^3.11.0"
   },