Update Libraries, Add Functions, and Modify Register Logic

[Trophy198]

1. Add push-receiver-v2 library and remove old libraries

2. Update externals for push-receiver-v2

• Adjust external dependencies for push-receiver-v2 integration

3. Add btoa encoding function

4. Update register send method

• Modify the method used for sending register data

5. Add firebase config and update register logic

• Incorporate firebase configuration
• Revise the registration logic to align with new firebase config

6. Update credential formatting and add loading UI while fetching commands

• Correct credential formatting according to new standards
• Introduce a loading UI to enhance user experience during command fetching