woodruffw / rsus

* shard: keep things recent

* workflows/ci: disable schedule

* shard: update lockfile

* rsus/config: use YAML::Serializable

Take 3.

This allows KEMAL_ENV to be set within config.yml.

RSUS currently logs a limited set of events in JSONL format:

* `startup` events (logged whenever `rsus` is run)
* `post` events (logged whenever the upload endpoint is hit)
* `slugify` events (logged whenever a new file slug is generated)
* `upload` events (logged whenever the upload process begins
(post validation + auth))
* `error` events (whenever something fails, besides 404)

This allows a (future) logging system to display a friendly username,
rather than the user's auth token.

cURL (and probably other HTTP clients) don't always send the right
or most-accurate Content-Type, so try to guess it from the suffix
of the uploaded file.

See curl/curl#2280

The filename is used to build both the filepath and the URL.