Path With Minimum Effort

You are a hiker preparing for an upcoming hike. You are given `heights`, a 2D array of size `rows x columns`, where `heights[row][col]` represents the height of cell `(row, col)`. You are situated in the top-left cell, `(0, 0)`, and you hope to travel to the bottom-right cell, `(rows-1, columns-1)` (i.e., **0-indexed**). You can move **up**, **down**, **left**, or **right**, and you wish to find a route that requires the minimum **effort**. A route's **effort** is the **maximum absolute difference**** **in heights between two consecutive cells of the route. Return _the minimum **effort** required to travel from the top-left cell to the bottom-right cell._   **Example 1:** **Input:** heights = [[1,2,2],[3,8,2],[5,3,5]] **Output:** 2 **Explanation:** The route of [1,3,5,3,5] has a maximum absolute difference of 2 in consecutive cells. This is better than the route of [1,2,2,2,5], where the maximum absolute difference is 3. ``` **Example 2:** **Input:** heights = [[1,2,3],[3,8,4],[5,3,5]] **Output:** 1 **Explanation:** The route of [1,2,3,4,5] has a maximum absolute difference of 1 in consecutive cells, which is better than route [1,3,5,3,5]. ``` **Example 3:** **Input:** heights = [[1,2,1,1,1],[1,2,1,2,1],[1,2,1,2,1],[1,2,1,2,1],[1,1,1,2,1]] **Output:** 0 **Explanation:** This route does not require any effort. ```   **Constraints:** - `rows == heights.length` - `columns == heights[i].length` - `1 <= rows, columns <= 100` - `1 <= heights[i][j] <= 106`