[lua, cpp] Assault Containerization + Framework

[CriticalXI]

I affirm:

• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

• Continues the work done by @dallano to allow Assaults to utilize the container framework.
• Corrects an issue with mobs in instances roaming slightly at the start by setting battlefield mobs to have 0 roam distance along with 0 max roam distance.
• Fixes an issue with AfterZoneIn triggering updateCharLevelRestriction against players which would remove the existing level restriction placed on players.
• Follow up PR coming converting all of the existing Assault IDs.lua to not utilize hard coded IDs and making the first initial Assault in this setup.

Steps to test these changes

• Not currently testable, will be following up with another PR with initial assault mission to showcase utilizing this new framework.

[Frankie-hz]

Mobs in assaults are supposed to roam, at least for most of them. I would remove this and apply it per assault if its needed.

[CriticalXI]

Main difference is that the mobs that need to roam in instances just need to not have the MOBTYPE_BATTLEFIELD not set in mob_pools. Unless there's a more obvious way to go about this. I just noticed this broke for mobs that do have that mobtype set in instances were still roaming when they shouldn't when I was testing this didn't break other instances.