V.2.12.0

Changes

• Redid internal types.
• Changed client script loading to use RunContext.
• Deprecated bundled Nexus VR Core version in favor of games pulling in their own static version.
  • Nexus VR Core won't be removed due to backwards compatibility, but the stability of the API will not be guaranteed into the future.
• Removed legacy chat window due to upcoming removal (https://devforum.roblox.com/t/migrate-to-textchatservice-removing-support-for-legacy-chat-and-custom-chat-systems/3237100).