Optimisation: Improve payload size for bundled toiletmap geohash tiles

[ob6160]

• When users are zoomed quite far out on the map, we still request the full list of compressed toilets for that tile. As all of these toilets are bundled under a single marker with a count in it, all we need to send to the client technically is a count of all of the toilets in the tile and the filter information

Illustrated example:

The API request for map tiles inside the geohash chunk gcp: loosByGeohash(geohash: "gcp").
This returns:

{
  "data": {
    "loosByGeohash": [
      "d22dc2b7d54fbb051da3ec7a|gcpvqkenb|49",
      "a8567086272989f6f06aa058|gcpvqm6xe|1",
      "b2725a08106421713fa6f0f1|gcpvqmg5g|1",
      "709f062960c8bc7bdeafafc3|gcpvq8gqw|1",
      "10c29fc18441c37efdbc34e1|gcpvqqgfg|1",
      "4468c8529e2376da9c205a02|gcpvqxk7e|49",
      "aa3c3472650826b8888f347a|gcpvqq33y|1",
      "0f08412b247e2e35a9c7cd18|gcpvqeu7w|25",
      "83c0a588c695fc3eb898060a|gcpvq43n2|57",
      "30afad2199fdbd607614dbbc|gcpvq09sk|39",
      "90790b0b22360453da4a34df|gcpvqw5m4|0",
      "d8eacfc55052ba8870507387|gcpvqfd78|0",
      "95830cff872de065172ca72e|gcpvqybe0|9"
.... many more records
    ]
  }
}

This change proposes that we extend the API to only return the count of loos, instead of the information - because it won't be rendered until the user zooms in further.

Some questions will need to be answered about how we can tell if all of the loos inside of the geohash tile will be rendered in a bundle by Leaflet, as this will determine whether we ask for the count request or not.

I'm pretty sure that we can use this technique safely for when users are zoomed out quite far.. in scenarios like this: