Save which agent is running a task. This is now visible in the admin UI
in the queue and in the agent details screen.
# changes
- [x] save id of agent executing a task
- [x] add endpoint to get tasks of an agent for #999
- [x] show assigned agent-id in queue
- [x] (offtopic) use same colors for queue stats and icons (similar to
the ones used by pipelines)
- [x] (offtopic) use badges for queue labels & dependencies
- allow repo names to be case-insensitive
- improve backend error handling on DB get errors (record not found ->
404, else -> 500)
- replace magic numbers of http response codes
- unify the look and feel of cancel / save buttons on forms and view
them in one line
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Co-authored-by: Lauris BH <lauris@nix.lv>
