In a medium pot over medium-high heat, brown chicken in olive oil, about 3 minutes a side. (Chicken does not have to be cooked through.) Remove from pot, turn heat to medium-low, add onion, garlic and ginger. Cook until soft. Remove garlic halves and smush in Thai curry paste until blended. Chop or pull apart chicken, then add it back to the pot along with broth. Simmer until chicken is cooked through. Add noodles then vegetables in shifts (with firmer ones, like carrots, going in earlier than tender ones, like greens) and cook until tender, about 4 minutes. Whisk in miso and coconut milk. Serve topped with lime and cilantro.