Update TPP service to fully support multiple regions

[marip8]

Consider updating the TPP service definition to fully support multiple selection regions. Currently we concatenate all rasters into a single "super raster" here, which forces all regions to be planned together. I think we have a couple options for implementing this change:

• Change the current service definition to return a vector of vector of tool paths; add a BT node to concatenate tool paths to maintain the current behavior
• Add a new service definition for tool path planning that returns the vector of vector of tool paths