Add bundle-size and create-plugin-update workflows #319

This project is lacking bundle-size and create-plugin-update workflows that can help with maintenance and reviewing frontend bundle size impact in PRs.

Please see each readme to understand how to add them to this project:

• Bundle Size Readme
• Create Plugin Update Readme

Note that the bundle size workflow expects "main build information" to be stored in gh action artifacts which means you will need to build the plugin on merges to main and then upload the built artifact to gh. The readme troubleshooting section should help explain how to implement this.