Add a "Baking Node" in the Shader Editor

Right now, the baking workflow is very tedious and despite some addons to help with that, having a node that would collapse a branch of the shader graph into a texture or into vertex color would be very useful.

• Support multiple baking nodes per shader graphs
• As an RGBA input
• As a passthrough and/or a baking result output
• As a dropdown to choose Vertex or Texture baking
• As a field for the texture reference or vertex color group reference (where the data is stored)