Other MSG types

[ExpHP]

There are "ending" .msg files with different instructions from the main .msg files.

There are also staff.msg. Not sure if these are similar to "ending" or their own thing entirely.

All scene games have either a mission.msg or titlemsg.txt. These aren't even related to other MSG files at all (just a container for a bunch of strings) but it'd be nice to parse them into a meta.