A Shortest-Path CLI in Rust — Making a Min-Heap from a Max-Heap, Path Reconstruction, and Rejecting Negative Weights

A CLI that finds shortest paths in a weighted graph, in Rust, with Dijkstra's algorithm. Three implementation hinges: (1) Dijkstra needs a min-priority-queue to pull the closest unfinalized node, but Rust's BinaryHeap is a max-heap — so you reverse the Ord, (2) record predecessors to reconstruct the