refactor: update text size and punctuation in previews

Increase text size from 16 to 32 in the "Height diff" preview
to enhance readability. Change "!" to "." for consistent
punctuation in the "Punctuation Replacement" preview. These
changes improve the design aesthetics and maintain
consistency in visual presentations.

Author: iSapozhnik

Sources/TextDiff/TextDiffView.swift

@@ -130,7 +130,7 @@ public struct TextDiffView: View {
 }
 
 #Preview("Height diff") {
-    let font: NSFont = .systemFont(ofSize: 16, weight: .regular)
+    let font: NSFont = .systemFont(ofSize: 32, weight: .regular)
     let style = TextDiffStyle(
         additionsStyle: TextDiffChangeStyle(
             fillColor: .systemGreen.withAlphaComponent(0.28),
@@ -152,16 +152,15 @@ public struct TextDiffView: View {
     )
     ZStack(alignment: .topLeading) {
         Text("Add ed a diff view. It looks good! Add ed a diff view. It looks good!")
-            .font(.system(size: 16, weight: .regular, design: nil))
+            .font(.system(size: 32, weight: .regular, design: nil))
             .foregroundStyle(.red.opacity(0.7))
 
         TextDiffView(
-            original: "Add ed a diff view. It looks good! Add ed a diff view. It looks good!",
+            original: "Add ed a diff view. It looks good! Add ed a diff view. It looks good.",
             updated: "Add ed a diff view. It looks good! Add ed a diff view. It looks good!",
             style: style,
             mode: .character
         )
     }
     .padding()
-    .frame(width: 320)
 }