Complete the MFE conversion process

[jmakowski1123]

Problem

The micro-frontend project started in 2018, with the stated goal of migrating all of the Open edX user-facing pages to the MFE architecture. While good progress has been made, there's still a lot to do. The amount of frontend-related technical debt in edx-platform hinders development of new features and maintenance of existing ones

Product/Platform Value

As many items here, this ultimately has a direct impact on adoption by making development of new features easier. It is, after all, the main motivation behind the move the micro-frontends.

Acceptance Criteria

### Sub-epics:
- [ ] https://github.com/openedx/edx-platform/issues/31624
- [ ] https://github.com/openedx/public-engineering/issues/219
- [ ] https://github.com/openedx/edx-platform/issues/32692
- [ ] https://github.com/openedx/edx-platform/issues/31620
- [ ] https://github.com/openedx/platform-roadmap/issues/322
- [ ] https://github.com/openedx/public-engineering/issues/53
- [ ] https://github.com/openedx/edx-platform/issues/31623
- [ ] Remove frontend support from course-discovery service
- [ ] Replatform legacy Credentials pages into micro-frontends
- [ ] Remove frontend support from credentials service
- [ ] Replatform legacy Ecommerce pages into micro-frontends
- [ ] Remove frontend support from ecommerce service
- [ ] (Any other missing steps?)

Related or in-progress work

2U currently owns this, but has insufficient resources to take it to completion.

Contingencies

https://github.com/openedx/tcril-engineering/issues/432

[kdmccormick]

I fleshed out the Acceptance Criteria of this initiative with all the relevant high-level epics that I'm aware of.

[dianakhuang]

FYI for tracking edx-platform endpoints: https://openedx.atlassian.net/wiki/spaces/COMM/pages/3712680008/LMS+Endpoints+Rendered+By+Django