move build of ember-debug to rollup

[mansona]

Context

The ember-inspector codebase is structured by two main pieces: the UI app (what you see when you use the inspector extension), and the ember_debug folder (code that is built then bundled into an ember_debug.js script, then injected in the page at runtime to create the bridge between the Ember app you want to inspect and the inspector extension).

Description

As part of the ultimate goal of Ember+Vite apps support, this PR changes the way ember_debug folder is built.

• Before, the build was included in ember-cli-build. In other words, the inspector UI and the ember_debug were one package sharing the same build pipeline.
• Now, the ember_debug is a separate package that has its own build pipeline relying on Rollup. At this stage of the work, the ember-cli-build remains responsible for the ember_debug.js bundle (this will be reworked in a later PR).

Ultimately we will need the injected script to be type=module to be able to use the required top-level await() to support Vite, but for now we can keep it as AMD but move the build over to Rollup.

This change should not be breaking in any way so any regressions are unexpected 👍

[BlueCutOfficial]

@mansona A suggestion of description that you're free to modify 😇 🙏

---

Done ✅

[BlueCutOfficial]

Following the rebase, we now have to fix an issue with these lines:

const emberDebug = requireModule('ember-debug/main')['default'];
const viewInspection = emberDebug.viewDebug.viewInspection;