feat: add blur node

[the-eater]

This feat adds a blur node that will blur any region underneath it, and handle damage tracking etc (because it already existed, and now I get to use it for free stolen from the other nodes)

Changes

• Add blur node
• Remove all blur logic from buffer and rect nodes
• Add clipping logic to both blur and texture pass

Fixes

• Fixes create blur_node #148 by adding the blur node
• Fixes Single pixel buffers aren't blurred #128 by decoupling blur from buffer/rect

Credit

@ErikReider once again for the struct linked_node

[WillPower3309]

Exactly what I was looking for! I do have a couple small comments though. Great work!

[WillPower3309]

Worth noting as well that the mask bit is irrelevant for RGBX, since we don't have opacity for those nodes (other than the opacity we pass, which would either make it translucent or completely transparent, so no need for masking)

[the-eater]

Worth noting as well that the mask bit is irrelevant for RGBX, since we don't have opacity for those nodes (other than the opacity we pass, which would either make it translucent or completely transparent, so no need for masking)

Yeah, it allows masking a RGBX texture, but not with a different RGBX texture

It's just covered in shader also, but none are linked with rgbx