UPDATE README: Firebase + Rapid API setup for new dashboard UI

[shreyas-damn]

• Description:

The Firebase and Rapid API dashboards have both gone through significant UI changes since the current documentation was written.
This causes confusion for new contributors trying to follow the setup process.
The goal of this issue is to update the README.md setup guide so that it accurately reflects the 2025 interface of both services.

[github-actions]

Thank you for raising this issue! Our team will review it soon.

For more queries or discussions or approval of requests, please join the Discord server for further discussion: https://discord.com/invite/Yn9g6KuWyA

[shreyas-damn]

@DhanushNehru I’d like to work on this issue as part of Hacktoberfest 2025