Optional methods to craft\base\Fs for client-side uploading (presigned upload URLs)

[timkelty]

A craft\base\Fs should be able to advertise the ability to upload via client-side upload, e.g. PUT to a pre-signed S3 URL).

Questions:

• How do we determine which upload method to use?
  • Frontend implementations can just hit the new controllers directly, but CP would need a config
    • per FS (probably easiest to start), per field, per action?

Additionally, nice-to-haves:

• scripts to be used/include on the frontend (ideally the same as what the CP uses)

Related:

• Support Direct File Uploads to Craft Cloud for Large Attachments verbb/formie#2318 (comment)
• Additional event after generating asset URLs #8784
• Handle large Asset uploads #9084
• Functionality to generate pre-signed URLs aws-s3#126
• Documentation on Craft Cloud asset uploading from front end contexts cloud#51