DoS considerations

[Swader]

The original idea I had was to automate (Github Action cronjob) the fetcher to append to an in-repo file and commit it once per minute. This would keep the tools as the canonical source of current remarks on the chain. However, if someone were to start uploading large files, that text file would get large fast, wrecking the repo and all tools that consume it.

Instead, the proposal is to:

• create a light-append mode which only appends information about when a remark took place, its type, and everything about it, but not the remark itself. The body would not be saved.
• ping a sidecar instance, like so: https://sidecar.rmrk.app/blocks/5393445 to retrieve the actual remark, regardless of its size