Replace user configuration with KDL and improve Rust source spacing

crates/ferese-layout/src/scrolling.rs

@@ -103,6 +103,7 @@ impl ScrollingLayout {
     pub fn set_default_width(&mut self, width: ColumnWidth) {
         self.default_width = normalized_width(width);
     }
+
     pub fn with_default_width(default_width: ColumnWidth) -> Self {
         Self {
             default_width: normalized_width(default_width),