Summary:
- Supports auto-completion
- Supports various keyboard interactions to delete/select/copy-paste tokens
- Supports various mouse interactions to select and move tokens.
- Supports undo/redo while editing tokens.
Test Plan: stand-alone fixture and browser test verify the supported behaviors
Reviewers: paulfitz
Reviewed By: paulfitz
Differential Revision: https://phab.getgrist.com/D2789