Multiplayer Playmode SDK 2.0.0

Added Multiplayer local simulation mode to server local instances.

When deploying remote instances, automatically create a fleet with the correct architecture based on the server's build profile (for example, if building for ARM64, automatically creates an ARM64 fleet).

This version only supports Unity 6.3 and beyond.

Migrated most of the code to the engine into the Play Mode Framework and the Multiplayer modules. This change is laying the foundation for a more stable and open Play Mode experience.

Updated minimum version of Multiplayer Services packages to 1.2.0-pre.1.

Fixed an issue where the clone editor's audio toggle would reset every time scripts were reloaded.