Mods that offer a buff while aiming should have a UI indicator when they're active

[SasoDuck]

Mods such as Critical Focus, Market Target, and Resolute Focus offer bonuses only while aiming.
Unfortunately, there is no UI indication of this when you aim, so unless you've memorized your builds or check every time before going into a mission (who wants to do that?), it can be hard to remember if you're using a build that requires aiming to take full advantage.

Please add a HUD icon to the buff list by your health for these mods that appears when you're aiming so you know when these types of mods are engaged.
Alternatively, some sort of a crosshair effect could also work.