Revert "Consolidate content versioning"

[paescuj]

Reverts #22227

The PR requires some finishing touches before we can release it, for example

• need to verify whether it is always correct to stringify the JSON value in the migration, even on DBs that have native JSON support:

  directus/api/src/database/migrations/20240415A-consolidate-content-versioning.ts

  Line 20 in adeccb7

  .update({ delta: JSON.stringify(finalVersionDelta) })

• the save method now requires update permission on directus_versions - e.g. disregard permissions for the update call (need to check whether that is safe) or make it a breaking change, ...
• the save return value is currently broken (shouldn't be critical for app though, just when using the api)

[br41nslug]

@paescuj can you elaborate on those 2 potential issues so they can be addressed instead of reverted? (the json things should be fine)