Fixes #37798 - Fix AngularJS handling of AK CVEs and add warning banner for multi-env AKs

[jeremylenz]

What are the changes introduced in this pull request?

1. When you save an activation key, the AngularJS activation key details page has always sent incorrect content_view_id and environment_id params which didn't match the environment and content_view nested params. Example:

"content_view_id"=>3,
 "content_view"=>{"id"=>2, "name"=>"cv2"},
 "environment_id"=>5,
 "environment"=>
  {"library"=>false,
   "registry_name_pattern"=>nil,
   "registry_unauthenticated_pull"=>false,
   "id"=>2,
   "name"=>"dev",

(note the nonmatching IDs)

The API previously compensated for this, until #11135. Now, we compensate for it again.
2. Add a warning banner to the activation key details page:

3. Ensure that you can make other edits to activation keys without overwriting the AK's content view environments.

Considerations taken when implementing this change?

This is somewhat of a stopgap for the UI until we can get true multi-environment display built. The plan is

1. fix what's broken and warn about known issue <-- you are here
2. display multi-env AKs in the web UI <-- future
3. allow you to change CVEs of multi-env AKs in the web UI <-- future

What are the testing steps for this pull request?

Create a multi-CV activation key
Make an edit to the description or other AK fields
Ensure that the AK remains a multi-CV AK (you can check by looking for the banner, or looking at the API response multi_content_view_environment value
Ensure that you can change an AK's single cv/lce with no errors
Ensure that you can change a multi-env AK's cv/lce in the web UI. This will cause it to become a single-env AK; this is expected (you didn't read that banner, did you? ;)

[chris1984]

Code looks fine, starting to test

[chris1984]

APJ works fine, left 2 small questions