Extend the GeoProcessing tool to work with client side Vector layers as WPS inputs

[MV88]

Description

It is requested a new additional feature based on the recently developed GeoProcessing tool for supported Intersection and Buffer processes.
The existing tool functionalities are expecting to be used only for WMS and/or WFS layers in TOC as inputs for aforementioned processes.
As part of this work it is requested to extend the current tool to also support vector layers defined or imported on the client side.

Possible use case scenarios to supports are:

• Use the output of the GeoProcessing tool (vector layers generated by a buffer or intersection geoprocess) for performing another operation using it as a new input
• Use an imported vector layer (SHP, GeoJson, KML etc) as an input for the GeoProcessing tool
• Use existing annotations as an input for the GeoProcessing tool (to check if possible, it could be excluded initially since we have a new implementation in master)
• Use vector layers TOC coming from measurements

In all cases the UX should be the same and well consistent.

Acceptance criteria

• Allow local vector layers listed above to be used as input in the GeoProcessing plugin
  • measurements
  • imported GeoJSON
  • imported Shapefiles
  • other imports
  • annotations
• make sure that the CollectGeometries request sent to the backend is adapted for vector layers
• handle cases where Geometry collection is generated from a vector layer, because buffer and intersect processes fails with it, we should prevent the user to click run and notifying it via user feedback
• for intersection it should maintain the previous checks we do, first layer/ feature can't be a point
• Add possibility to configure a predefined geoserver url to be used as a fallback within process requests when the source layer is a local vector layer

Other useful information

[tdipisa]

@ElenaGallo take care of this #9691 (comment) for the related documentation.