Dedicated server support first pass - part 2/2 New DGS flow [MTT-1936]

[SamuelBellomo]

Description

This PR adds the new flows necessary for boss room to start a dedicated server. This adds

• A new scene to bypass the main menu and new connection states. server character selection scene is now managed automatically when finishing a game.
• Adding command line args for Multiplay hosting.
• Prevent closing lobby if no player is in it in DGS mode.
• Adding flow post game to automatically bring everyone back to char select.
• This also adds instructions for users for logging.
• WaitForServerStarted is introduced as a new pattern to help alleviate callback hell.
  • --> this is reeaaally open to design discussions, I'm not super attached to this.

This is a simplified branch to help with review. Original work branch for history purposes: origin/sam/feat/dedicated-server-support

TODO SAM before merging this

• [x] add tests after LP's connection management tests are merged.
• [x] add full flow tests like we're doing with host tests, to at least check that we can start a DGS
• [x] add tests for WaitForServerStarted
• [x] add doc for WaitForServerStarted
• [x] add new doc or instructions for how to setup boss room with DGS

Issue Number(s)

MTT-1936

Contribution checklist

• [x] Tests have been added for boss room and/or utilities pack
• [x] Release notes have been added to the project changelog file and/or package changelog file
• [x] Pull request has a meaningful description of its purpose
• [x] All commits are accompanied by meaningful commit messages
• [x] JIRA ticket ID is in the PR title or at least one commit message
• [x] Include the ticket ID number within the body message of the PR to create a hyperlink