Neighbours list based on distance bounds

Creating centroids from sf polygons:

(centroids <- st_centroid(map_geom))
## Geometry set for 49 features 
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 6.221943 ymin: 11.01003 xmax: 10.95359 ymax: 14.36908
## CRS:           NA
## First 5 geometries:
## POINT (8.827218 14.36908)
## POINT (8.332658 14.03162)
## POINT (9.012265 13.81972)
## POINT (8.460801 13.71696)
## POINT (9.007982 13.29637)