Added the ImageWidth enumeration to the Website library target.

Services/Website/Tests/Library/Cases/Internal/Enumerations/ImageWidthTests.swift

@@ -0,0 +1,24 @@
+import Testing
+
+@testable import WebsiteLibrary
+
+@Suite(
+    "ImageWidth enumeration",
+    .tags(.enumeration)
+)
+struct ImageWidthTests {
+
+    // MARK: Computed tests
+
+    @Test(arguments: zip(
+        ImageWidth.allCases,
+        [480, 800, 1200]
+    ))
+    func `width`(
+        for imageWidth: ImageWidth,
+        expects width: Int
+    ) {
+        #expect(imageWidth.width == width)
+    }
+
+}