allow simplify function to work on selected nodes

hello friends

we need to be able to use the simplify function to only the selected nodes, not the entire shape selected I mean to have 2 entries in the menu

• [simlify shape]
• [simplify selected nodes]
• we could also provide a button for it for easy access in the node tool option bar

because most of the time especially after performing boolean operations only specific sections need cleaning, not the entire shape path, and if you apply the normal simplify it fixes one section and damages the other