Photo Metadata Picker

Choose Media library, with nearby photographs as the widget for a media reference field. Below the usual media library it lists photographs within a radius of the content being edited, nearest first, each with a "Use this photo" button that adds it through the media library's own selection, so cardinality, access and validation all still apply.

Where content is

Worked out by origin sources, asked in priority order:

Priority	Source
300	A geofield on the entity being edited: the unsaved value in the form, then the saved one
100	A geofield on an entity it references (media references excluded)

The editor is always told which source answered. Add a source for content that is located some other way by implementing Drupal\photo_metadata_picker\Origin\OriginSourceInterface and tagging the service photo_metadata_origin with a priority.

Views

View	Path	For
Photo library	/admin/content/media/photos	Filter by keyword, date, credit and whether a photo has coordinates. Its proximity display is what the widget embeds.
Photo map	/admin/content/media/map	Where photographs were taken. Installed only with Leaflet Views.
Photo metadata gaps	/admin/content/media/photo-gaps	What arrived without usable metadata, as a worklist.

The widget's view is a setting, so a site can point it at its own.