refactor(server): Better Way of getting players

[Mycroft-Studios]

Describe Pull request
Refactors the way the admin menu handles user data.
the current way causes huge crashes when dealing with a large amount of users, (see #224 )
this should help reduce this, aswell as have some performance benifits aswell.

If your PR is to fix an issue mention that issue here

Questions (please complete the following information):

• Have you personally loaded this code into an updated qbcore project and checked all it's functionality? Yes
• Does your code fit the style guidelines? yes
• Does your PR fit the contribution guidelines? yes