Extract Coordinate, IntegerRange and Coordinate3d to new AdventOfCode.HelperClasses project and refactor solution for modularity and type consistency

AoC_2025/Day04.cs

@@ -1,8 +1,5 @@
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using AdvenOfCode.Contracts;
-using Coordinate = (int x, int y);
+using AdvenOfCode.Contracts;
+using AdventOfCode.HelperClasses;
 
 namespace AoC_2025;
 
@@ -64,7 +61,7 @@ public class Day04 : IPuzzleSolver<long>
     {
         var indexedCharacters = gridLine.Index();
         var validRolls = indexedCharacters.Where(tuple => tuple.Item == '@');
-        var rollCoordinates = validRolls.Select(tuple => (xIndex, tuple.Index));
+        var rollCoordinates = validRolls.Select(tuple => new Coordinate(xIndex, tuple.Index));
         return rollCoordinates;
     }
 
@@ -79,12 +76,12 @@ public class Day04 : IPuzzleSolver<long>
     {
         Coordinate[] neighbourDirections =
         [
-            (-1, -1), (-1, 0), (-1, 1),
-            (0, -1),               (0, 1),
-            (1, -1),  (1, 0),  (1, 1),
+            new(-1, -1), new(-1, 0), new(-1, 1),
+            new(0, -1),              new(0, 1),
+            new(1, -1),  new(1, 0),  new(1, 1),
         ];
         var possibleNeighbours = neighbourDirections
-            .Select(direction => (coordinate.x + direction.x, coordinate.y + direction.y));
+            .Select(direction => coordinate + direction);
         var actualNeighbours = possibleNeighbours
             .Where(coord => coordinates.Contains(coord))
             .ToArray();