[FEATURE] Support event notification (e.g. for S3) by exposing a webhook

[badmonster0]

Original request from Discord:

I think the only immediate request I would have is maybe consider adding minio event support. I use minio locally and it supports events, just not through sqs.

Currently S3 supports event notifications by SQS. Users may want a different queue system, e.g. they use minio which can publish notification by webhook. We want expose a webhook API and route it specific sources.

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