Leetcode 1368. Minimum Cost to Make at Least One Valid Path in a Grid

Given a grid where each cell points to a neighbor and flipping a cell's arrow costs 1, find the minimum number of flips needed to create any path from the top-left to the bottom-right. This is a shortest-path problem on a directed grid where moves that follow a cell's arrow cost 0 and other moves cost 1 (solvable with 0-1 BFS or Dijkstra).