feat(grid): the coloured grid axis lines can be turned off (#1815)

Drafting Settings > Snap and Grid gains "Display grid axis lines",
kept with the other grid settings; the grid itself stays as it is.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/ui/overlay.rs

@@ -316,6 +316,8 @@ pub struct CrosshairOptions {
 pub struct GridStyle {
     pub opacity: u8,
     pub bg_luminance: f32,
+    /// Draw the coloured X/Y axis lines through the grid origin.
+    pub axes: bool,
 }
 
 impl Default for GridStyle {
@@ -323,6 +325,7 @@ impl Default for GridStyle {
         Self {
             opacity: 18,
             bg_luminance: 0.15,
+            axes: true,
         }
     }
 }
@@ -2722,7 +2725,7 @@ fn draw_grid(
         });
         frame.stroke(&path, major_stroke);
     }
-    if geometry.axis_extent > 0.0 {
+    if style.axes && geometry.axis_extent > 0.0 {
         let (gx, gy, gz) = grid_axes;
         let extent = (geometry.axis_extent + step_x.max(step_y)) * 1.5;
         draw_axes(

src/ui/window/drafting_settings.rs

@@ -35,6 +35,7 @@ pub struct DraftingSettingsState {
     pub grid_major_input: String,
     pub grid_adaptive: bool,
     pub grid_beyond_limits: bool,
+    pub grid_axes: bool,
     pub isometric: bool,
     pub iso_plane: IsoPlane,
     pub snap_angle_deg: f32,
@@ -72,6 +73,7 @@ impl DraftingSettingsState {
             || self.grid_major_input != saved.grid_major_input
             || self.grid_adaptive != saved.grid_adaptive
             || self.grid_beyond_limits != saved.grid_beyond_limits
+            || self.grid_axes != saved.grid_axes
             || self.isometric != saved.isometric
             || self.iso_plane != saved.iso_plane
             || (self.snap_angle_deg - saved.snap_angle_deg).abs() > 0.001
@@ -387,6 +389,14 @@ pub fn view_window<'a>(
                 ]
                 .spacing(6)
                 .align_y(iced::Center),
+                row![
+                    checkbox(state.grid_axes)
+                        .on_toggle(|_| Message::DraftingSettingsToggleGridAxes)
+                        .size(14),
+                    text(crate::t!("Display grid axis lines")).size(11),
+                ]
+                .spacing(6)
+                .align_y(iced::Center),
             ]
             .spacing(6),
         );