fix: search example to support Redis v4+ and Express 4/5

[vinybk]

This PR updates the Search example to address issues caused by breaking changes in Redis v4+ and Express 5.

Key changes include:

• Replacing sadd with sAdd and smembers with sMembers for Redis v4+ compatibility.
• Using {0,1} syntax for optional parameters instead of ? to support Express 5.
• Adding error handling for Redis connection and commands.

These changes ensure the example works seamlessly.

Tested locally with: Redis 7.0.15 Node.js 22.12.0 Express 5.0.1 and 4.21.2 Debian 12

Note: Adding automated tests for this example could help catch issues like this sooner. If you think it's worthwhile, I’d be glad to help implement them.

[vinybk]

Hi @wesleytodd, I've made the requested changes:

• Updated optional route syntax to /{:query}.
• Refactored Redis initialization into a dedicated function initializeRedis to make sure that it completes before the server starts.

I think this aligns with your feedback, but please let me know if I misunderstood or missed anything. Thanks!