227. Food Delivery Route Optimizer

Write a function solve that finds the shortest route to visit all delivery locations. Given starting point [x, y] and delivery locations [[x1,y1], [x2,y2], ...], return the minimum total distance using Manhattan distance.

Example:
Input: start = [0,0], locations = [[1,1], [2,0]]
Output: 4 (0,0 → 1,1 → 2,0 costs 2+2=4)

Run this challenge interactively in Python or JavaScript when the app loads.