Improve New UI Rebuild Performance

[bryanculver]

Proposed Changes

Either:

• Eject our React app to fix this bug (CRA is dead) so we can improve rebuild time: fix: production mode cache invalid  facebook/create-react-app#12391
• For 2.0.0, stop rebuilding the new UI on every start until we can address the above

This is a time-boxed story: If we can't reasonably do option one in the time permitted, switch to option two as a stop-gap and we can revisit option one in a fast follow-up.

Justification

The developer side and app start-up are slow because every post_upgrade is doing a full rebuild of the UI, even if things are unchanged. In 2.0.0 there won't really be anything to rebuild.

[gsnider2195]

Create React App appears to be dead.

[bryanculver]

Ejecting documentation: https://create-react-app.dev/docs/available-scripts/#npm-run-eject

[gsnider2195]

Potential path forward (next.js with react-router): Building a single-page application with Next.js and React Router

Links to Replacing Create React App with the Next.js CLI

[bryanculver]

Today:

We have #4214 but requires more time to review and document which parts are coming in from ejecting and which parts are overridden by us (because of CRACO/other overrides). We will commit time to review the PR (2 story points), ensure it has proper documentation, and move forward with that approach.

Future Story:

We can eject and own our build tools (build) vs find a replacement for Create React App (buy).

To quote @jathanism:

We bought something and the company went out of business.

We need to figure out what we're taking on with either approach:

Build: We accept an amount of tech debt and knowledge and understanding on how to continue building what we need with the tools and dependencies we have (or evolving them).

Buy: Find a replacement of CRA/CRACO that offloads a larger amount of the maintenance of the tools for a client-side app to reduce the overhead.

[glennmatthews]

Implemented by #4214.