Icons: Add Links Cut icon to Node Editor, plus other tweaks

- Tweaks to Paint Mode Fill and Sample tool icons
- Tweaks to GP Add Primitive icons

release/scripts/startup/bl_ui/space_toolsystem_toolbar.py

@@ -1387,7 +1387,7 @@ class _defs_node_edit:
     def links_cut():
         return dict(
             text="Links Cut",
-            icon="ops.mesh.knife_tool",
+            icon="ops.node.links_cut",
             widget=None,
             keymap="Node Tool: Links Cut",
         )

source/blender/editors/datafiles/CMakeLists.txt

@@ -723,6 +723,7 @@ set_property(GLOBAL PROPERTY ICON_GEOM_NAMES
 	ops.mesh.spin
 	ops.mesh.spin.duplicate
 	ops.mesh.vertices_smooth
+	ops.node.links_cut
 	ops.paint.vertex_color_fill
 	ops.paint.weight_fill
 	ops.paint.weight_gradient