Add Uptime Kuma to Monitoring section

[Raynzler]

Adding Uptime Kuma to the Monitoring section. It's a popular self-hosted monitoring solution with 75k+ GitHub stars that was missing from the list.

• Modern, actively maintained monitoring tool
• MIT licensed
• NodeJS based
• Clean web UI with mobile support

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Please take some time to answer the following questions as best you can:

• Why is it awesome?

Uptime Kuma provides a modern, user-friendly alternative to traditional monitoring tools. It offers a clean web UI, real-time updates via websockets, and supports 90+ notification services out of the box. With 25k+ GitHub stars and active development, it's become a go-to solution for many sysadmins looking for lightweight monitoring.

• Have you used it? For how long?

Yes, It's been a week now.

• Is this in a personal or professional setup?

Personal yes, I am exploring and working on some issues to fix here in the service.

• How many devices/users/services/... do you manage with it?

I don't use it for managing prod level stuff, I am an upcoming indie dev.

• Biggest pros/cons compared to other solutions?

Pros: Extremely easy to set up (single Docker container), intuitive UI, rich notification options, low resource usage, and active community support.
Cons: Less suitable for enterprise-scale deployments compared to solutions like Zabbix, limited historical data analysis features.

• Any other comments about your use case, things you've found excellent, limitations you've encountered... ?
  The 2FA support and multiple status page options are excellent for client-facing monitoring. The mobile-responsive design makes it easy to check status on the go. Would benefit from more advanced alerting logic, but the simplicity is also its strength for most use cases.

[Technetium1]

Thanks for this PR, it would be an excellent addition. Please update the link to https://uptime.kuma.pet/ and add the GitHub link as Source Code before the license.