Yeah I agree with RedEco. I think shes saying she’s a front-line offensive class (i.e. that you would put into the front row in a Final Fantasy-style JRPG as opposed to a mage or archer that you’d put in the back row).
The use of ”avant-garde” to mean ”artistically innovative“ is a metaphor, comparing the artist to a soldier who goes out ahead of everyone else into dangerous territory.
Thanks for translating these by the way! I’m glad someone picked this up.