chore: add snackbar on annotation add

bugfix: hide region sidebar on start annotation mode

bugfix: context menu in threesurfer

chore: prettify freesurfer selector

feat: slight enh of perspective zoom behaviour

it also sets global nav state

invisible UI in mobile view

chore: typing for switchmap waitfor

refactor: individual annot export
refactor: annotation geometry & edit cls
bugfix: annots in other spaces
feat: store annts in local storage

- added point
- allow copy of string/json/sands

bugfix: regional receptor distribution