feature: method to filter out service account initiated comment threads from MR diff view
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### Release notes
Provide a method for users to ignore comments from "service account" in the MR diff view.
### Problem to solve
We use a bot reviewer called CodeRabbit, which is defined as a service account within our group. It generates a lot of per-line comments, obscuring comments from human reviewers. Our human reviewers would like to be able to quickly sift out to see only issues that their colleagues have flagged.
### Proposal
A checkbox or button to "exclude bot reviewers". This is what the widget currently looks like:
{width=261 height=120}
You could imagine a button to "hide service account-initiated threads" or a checkbox to hide them by default.
Note that a human user will often respond to comments from the CodeRabbit bot, for clarification or to tell it that we have chosen to ignore the issue. This means that a comment initiated by a bot might still have a comment from a non-bot user on it. Another human reviewer (other than the author or assignee of the MR), might also choose to engage on a service account-initiated thread. Nonetheless, it might be fine to just have an option to hide service account-initiated threads. A separate question is whether users should receive notifications for service account-initiated threads on their MRs, but this could be described in a separate feature request.
### Intended users
Humans reviewers
issue