Fix/189 misc quirks

[joshua-dean]

Fix misc quirks found in #175

Description

Closes #189. Might bundle this in #202.

Changes:

• Add AnnotationSizeCookie static class to manage the annotation display size
  • Previously this wasn't even working as the second field didn't contain expires=
• Add nullish coalescing operators where relevant
• Fix some comment structures broken by formatting
• Simplify drag state construction

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

Annotation size cookie now actually works