Three-Element Target Combinations

Warner Music Group may need to identify three compatible catalog attributes whose numeric scores reach a required total. Given an array of integers and a target value, return every unique combination of exactly three elements whose sum equals the target.

Formal Specification

Implement three_sum_target(nums, target).

• nums is a list of integers.
• target is an integer.
• Return a list of triplets, where each triplet contains three values from distinct array positions and sums to target.
• Return each value combination only once, even when duplicate values produce the same triplet.
• Each triplet must be in nondecreasing order, and the returned list may be ordered lexicographically.
• A value may appear more than once in a triplet only when it occurs at least that many times in nums.

You may reorder nums in place.