Add AddressSearch and ReverseGeocoder to 'SINGLE' mode of meldemichel

[dopenguin]

Summary

It was requested that a feature can be reverse geocoded and the address search can be used programmatically in mode SINGLE.
An addition to the API.md was redundant, as the programmatic usage has already been described in the README of @polar/plugin-address-search.

Instructions for local reproduction and review

• Add the mapInstance to the window object in packages/clients/meldemichel/example/single.html.
• Use the following code snippet to trigger the search.

window.$mapInstance.$store.dispatch('plugin/addressSearch/search', {
  input: 'Spitalerstraße 12',
  autoselect: 'first'
})

A pin should be set to Spitalerstraße 12 and the following fields should have a value

• vendor_maps_address_str
• vendor_maps_address_hnr
• vendor_maps_address_plz
• vendor_maps_distance_to

[warm-coolguy]

🚀 @dopenguin