feat: improve sync required detection

[LordOfPolls]

What type of pull request is this?

• Non-breaking code change
• Breaking code change
• Documentation change/addition
• Tests change

Description

Fixes a flaw in how the library determines if a interaction command sync is required. Previously it did not check subcommand descriptions, and the wrong name was used for localisations.

This PR makes it far easier to add new attributes to compare, plus it resolves the above.

Changes

• Seperate command comparison into _compare_commands
• Actually check subcommand descriptions
• Use correct key for localisations
• Refactor comparison list for easier expansion

Checklist

• I've formatted my code with Black
• I've ensured my code works on Python 3.10.x
• I've tested my code