Collection of optimizations

[EinS4ckZwiebeln]

Description

A collection of some minor optimizations for the client and server, like improved for loops, queries and other logic. I tested all of them, but please make sure you guys do as well, just to be sure everything's still working as intended.

Checklist

• [x] I have personally loaded this code into an updated qbcore project and checked all of its functionality.
• [x] My code fits the style guidelines.
• [x] My PR fits the contribution guidelines.