terminal: Screen opts is a structure

src/terminal/StringMap.zig

@@ -109,7 +109,7 @@ test "StringMap searchIterator" {
     defer re.deinit();
 
     // Initialize our screen
-    var s = try Screen.init(alloc, 5, 5, 0);
+    var s = try Screen.init(alloc, .{ .cols = 5, .rows = 5, .max_scrollback = 0 });
     defer s.deinit();
     const str = "1ABCD2EFGH\n3IJKL";
     try s.testWriteString(str);