Filter features for adaptation option list by region/basin/...

[tomalrussell]

Building on previous work to map and list adaptation options.

The new requirement here is to list (and rank) features within an area of interest (admin region, river catchment...) in addition to current filtering by sector, layer, asset type.

The motivating example is to explore areas for potential tree-planting for slope stabilisation to reduce risk of landslides, prioritising:

1. according to multiple criteria
   • infrastructure risk reduction benefits
   • cost of planting and maintenance
   • carbon, biodiversity benefits
2. within specific areas
   • Country
   • Region (admin 1)
   • Catchment (basins)

[tomalrussell]

ref nismod/irv-frontend#70 and #187