ASA: Add distance scale on map

[BAAlexK]

Describe the task As an end user I need to see the scale of the map relative to the zoom position So that I can judge distance to key geographical locations

Acceptance Criteria

• [ ] Use existing scale add-on for Open Layers
• [ ] Scale changes on zoom level
• [ ] Distance unit displayed in Kilometers (Km)
• [ ] Dynamically scale to 10s of Kilometers
• [ ] Ensure scale bar doesn't block user interaction

SME/User Contact (may want to use a persona to fill this in)

Additional context

• Change drop down to scale bar instead of scale line here: https://openlayers.org/en/latest/examples/scale-line.html

[rajpersram]

UX Design mockup for a distance scale has been created in Figma with additional notes in the yellow sticky underneath the image.