* [chore] Remove years from all license headers
Years or year ranges aren't required in license headers. Many projects
have removed them in recent years and it avoids a bit of yearly toil.
In many cases our copyright claim was also a bit dodgy since we added
the 2021-2023 header to files created after 2021 but you can't claim
copyright into the past that way.
* [chore] Add license header check
This ensures a license header is always added to any new file. This
avoids maintainers/reviewers needing to remember to check for and ask
for it in case a contribution doesn't include it.
* [chore] Add missing license headers
* [chore] Further updates to license header
* Use the more common // indentend comment format
* Remove the hack we had for the linter now that we use the // format
* Add SPDX license identifier
* replace media workers with just runners.WorkerPool, move to state structure, use go-sched for global task scheduling
* improved code comment
* fix worker tryUntil function, update go-runners/go-sched
* make preprocess functions package public, use these where possible to stop doubled up processing
* remove separate emoji worker pool
* limit calls to time.Now() during media preprocessing
* use Processor{} to manage singular runtime of processing media
* ensure workers get started when media manager is used
* improved error setting in processing media, fix media test
* port changes from processingmedia to processing emoji
* finish code commenting
* finish code commenting and comment-out client API + federator worker pools until concurrency worker pools replaced
* linterrrrrrrrrrrrrrrr
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Signed-off-by: kim <grufwub@gmail.com>
