feat: qb-vehiclekeys bridge

[Manason]

This PR adds backwards compatibility with qb-vehiclekeys events and exports to Give, Remove, & check if a player has keys to a certain vehicle plate. This is done by searching through the vehicles to find the vehicles with the matching plate and then invoking native qbx_vehiclekeys functions to handle the rest. This means that if multiple vehicles have the same plate, these compatibility functions will operate on all of them. The bridge can be enabled/disabled via convar.

Other misc refactors done as part of this PR to support the bridge:

• made fxmanifest files more specific
• made client HasKeys a global function
• renamed server/keys.lua keysList and keysLifeTime to better reflect their use
• moved server HasKeys to keys.lua
• added some early return conditions in keys.lua