Combine multiple lists of integers into a single list without duplicates. The resulting list should contain all unique values from all input lists.

Examples:

Input: list1 = [1, 2, 3] list2 = [2, 3, 4] list3 = [3, 4, 5] Output: [1, 2, 3, 4, 5] Explanation: All unique values from the three lists are included in the result Input: list1 = [10, 20] list2 = [20, 30] list3 = [] Output: [10, 20, 30] Explanation: Empty lists are handled properly, and duplicates are removed
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