[EPIC] Consolidate the TypeSpec onboarding process for Mgmt. plane

For the long term, the TypeSpec review should be handled by the Arm team. However, before that, we need to complete the following tasks:

- [ ] Address and resolve all mgmt. plane related TypeSpec issues.
- [ ] Prepare documents to facilitate the TypeSpec migration process.
- [ ] Craft detailed guidelines for conducting TypeSpec reviews.
- [ ] Update our Engineering System to effectively identify TypeSpec-related issues.
- [ ] Roll out instructional courses for ARM team to review TypeSpec PR.
- [ ] Provide assistance in reviewing and rectifying TypeSpec issues within service teams until the ARM team is ready to assume control of the review process.