Chore - Optimize net usage

[Malivil]

• Remove NW vars when the value does not need to be networked
• Swap NW to NW2 vars when the value is only needed for clients with this player in their PVS
• Swap NW vars to targeted net messages (SYNC system) when the value only needs to go to a limited set of players and doesn't need periodic resends
• Change usages of net.Write/ReadString for SteamID64s to the new net.Write/ReadUInt64 to save 80 bits per message
  • Update external roles for shared messages (like TTT_Deputized in JJ22, TTT_RoleChanged in Randomat)