A person who is apathetic yet exhibits an extroverted demeanor, possesses a talent for understanding others' intentions, and embodies pragmatic optimism could be described as a "socially perceptive pragmatist."
While there may not be a single term that encapsulates all those traits precisely, you could also consider terms like "observant extrovert" or "empathetic skeptic." Ultimately, the combination of qualities suggests someone who approaches social situations with a level of detachment but still engages positively and effectively with others.