Change object.file.uploaded event to file.uploaded, and document its existence

[hackartisan]

Descriptive summary

The name of this event is incongruous with the other event names, see list in https://github.com/samvera/hyrax/wiki/Hyrax's-Event-Bus-(Hyrax::Publisher)

The event is not included in that list, and needs to be

Acceptance Criteria/Expected Behavior

This is a code refactor

Rationale (for feature request only)

Consistency and documentation will help core and downstream developers

Related work

the event was introduced in #5321

[hackartisan]

Changing the name of this event is likely a breaking change. Wait for @dlpierce to weigh in.

[dlpierce]

We're gearing up for a major release anyways, so my vote is to proceed.

[hackartisan]

@dlpierce sounds good. Can you help specify this issue with respect to how and where the breaking change should be documented?

[dlpierce]

Let's make sure it is noted in the release notes and added to the newly minted upgrade guide

[hackartisan]

👍🏻 This will be release notes for a 5.0? Is there are draft for that somewhere?