[PLAT-1279] Feature/size mode

[TrevorBurgoyne]

Size mode

PLAT-1279

Description

• Add size_mode argument to the ULabel constructor, which allows users to specify how the size of annotations should be scaled when the zoom level is changed.
  • Options are fixed, zoom, and inverse-zoom.
  • When set to fixed, the line size of annotations will remain constant regardless of zoom level.
  • When set to zoom, the line size of annotations will increase with increased zoom level.
  • When set to inverse-zoom, the line size of annotations will decrease with increased zoom level.
• Prior behavior is equivalent to size_mode = "fixed".
• Cleanup of unused demo logic
• Close Full removal of annotation with "erase" tool breaks submission #220 by adding null catch
• Close Links to NPM / script version usage docs #211 by adding link to npm page

PR Checklist

• Merged latest main
• Version number in package.json has been bumped since last release
• Version numbers match between package package.json and src/version.js
• Ran npm install and npm run build AFTER bumping the version number
• Updated documentation if necessary (currently just in api_spec.md)
• Added changes to changelog.md

Breaking API Changes

no

[joshua-dean]

Adding @CarterSolberg as he worked on the deprecated version of a similar feature in the past

[joshua-dean]

Two small notes. Like the demo cleanup

[joshua-dean]

Also, I don't really foresee it being a need, but while we're here: can you think of any reason we'd want to scale the zoom and inverse-zoom settings?
Right now they're fairly subtle, so perhaps for some case of script-assisted zoom setting/background swapping a user might want the zoom to be more (or less) aggressive.

Definitely not necessary for this PR, but maybe worth thinking about.