[Feature] Add character icons to various places

[fribbels]

Motivation

Having character avatar icons helps important selectors stand out more

Objective

Add character avatar icons to the following places:

• Relics tab selected character

• Relics modal equipped character

• Character tab add/edit character modal

• Priority/Exclude selectors on optimizer tab, but ONLY for the dropdown options when the selector is open. Otherwise icons are too distracting for the optimizer form