Toggle button for MPA overlay

feature #502

Implemented MPA map UI.

Related Issue

Fixes #

[ ] I have read the contributor's guide.
[ ] I linked an issue in the previous section
[ ] I have commented on the linked issue
[ ] I was assigned the linked issue (not required)
[ ] I have tested the change to the best of my ability against the sandbox or a local build.

Optional items:

[ ] My change adds new text and requires a change to translations.
[ ] My change requires a change to the documentation.
[ ] I have submitted a PR to the documentation repo.
[ ] I was not able to test... (explain below, e.g. you did not have permissions to test a specific feature)
[ ] This change depends O-FISH Realm repository changes (explain below)
[ ] This change depends O-FISH Web repository changes (explain below)
Optional: Add any explanations here
Optional: Add any relevant screenshots here