Enable Pixel Snap by default in the 2D editor

Since this avoids accidentally placing 2D nodes at subpixel positions,
this results in more crisp visuals by default, even when pixel snapping
is disabled in the project settings.

(cherry picked from commit c03e7c2dde10c0981ae9db39e4e6a7a40838b3db)

editor/plugins/canvas_item_editor_plugin.cpp

@@ -5716,7 +5716,9 @@ CanvasItemEditor::CanvasItemEditor(EditorNode *p_editor) {
 	snap_rotation = false;
 	snap_scale = false;
 	snap_relative = false;
-	snap_pixel = false;
+	// Enable pixel snapping even if pixel snap rendering is disabled in the Project Settings.
+	// This results in crisper visuals by preventing 2D nodes from being placed at subpixel coordinates.
+	snap_pixel = true;
 	snap_target[0] = SNAP_TARGET_NONE;
 	snap_target[1] = SNAP_TARGET_NONE;