Add field machine name renaming feature

Postponed on ✨ Allow cloning a field to the same entity with a new machine name Active but we may already discuss and plan this feature!

Problem/Motivation

Need to change the machine name of an existing field is something every Drupal administrator runs into sooner or later. Still this is not possible in Drupal yet, which is a burden.

It would be great to provide such a functionality in this super helpful module, at least as a very technical tool with large WARNINGS ;)

There might be several strategies to rename a field machine name and probably the most promising is:

1. Clone the field to the same entity using the new machine name ( ✨ Allow cloning a field to the same entity with a new machine name Active )
2. Copy over the existing field (& revision) data
3. Delete the old field and its data

Steps to reproduce

Proposed resolution

Remaining tasks

1. Discuss
2. Implement
3. Test
4. Release

User interface changes

API changes

Data model changes