Generate source map during development

[bartbutenaers]

Description

During the Vite build phase, the frontend code is being minified. Which made it quite hard for me to contribute to this repo. This pull request uses the same mechanism as in the node-red-dashboard-2-ui-example repo to allow skipping minification during the development phase.

I have also added an extra (optional) step to the documentation, but imho the developing locally section should be not under third-party widgets, because it is also required when you want to contribute to the dashboard...

Related Issue(s)

See 819

Checklist

• [ X ] I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production

Labels

• Includes a DB migration? -> add the area:migration label

[joepavitt]

There is a difference in the instructions detailed in the Contributing Guide and the Third Party Widgets - developing locally section in that the latter installs node-red-dashboard via manage palette, the former installs the source code base for modifications directly to Dashboard itself.

So, the vite change you've made will effect core Dashboard, but the docs you updated refer to the UIExample repository. My understanding is that the UI Example repo does still offer this functionality, so they're valid updates, but we also need to update the base Contributing install instructions too please!

[bartbutenaers]

Based on this discussion on Discourse, I have updated the title and modifications in this PR.