[FF] `work_items_autocomplete` -- Enable work items in autocomplete and recent items search
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## Summary
This issue is to roll out [the feature](https://gitlab.com/gitlab-org/gitlab/-/issues/588616) on production,
that is currently behind the `work_items_autocomplete` feature flag.
## Owners
- Most appropriate Slack channel to reach out to: `#g_global_search`
- Best individual to reach out to: @sdungarwal
## Expectations
### What are we expecting to happen?
When enabled, the autocomplete and recently viewed items functionality will use WorkItems instead of Issues. This provides:
- Better support for work item types beyond issues
- Consistent API behavior across different work item types
- Improved global search capabilities
### What can go wrong and how would we detect it?
- **Data loss**: None expected, as work items are built on top of issues
- **Broken pages**: Autocomplete or recent items could fail to load
- **Performance impact**: Potential N+1 queries if authorization checks aren't optimized
Monitoring:
- Watch error rates on `/autocomplete` endpoints
- Monitor GraphQL query performance for `recentlyViewedItems`
- Check logs for authorization-related errors
## Rollout Steps
Note: Please make sure to run the chatops commands in the Slack channel that gets impacted by the command.
### Rollout on non-production environments
- Verify the MR with the feature flag is merged to `master` and has been deployed to non-production environments
- [ ] Deploy the feature flag at 50% with `/chatops gitlab run feature set work_items_autocomplete 50 --actors --dev --pre --staging --staging-ref`
- [ ] Monitor that the error rates did not increase
- [ ] Enable the feature globally on non-production environments with `/chatops gitlab run feature set work_items_autocomplete true --dev --pre --staging --staging-ref`
- [ ] Verify that the feature works as expected in `staging-canary`
### Specific rollout on production
For visibility, all `/chatops` commands that target production must be executed in the [`#production` Slack channel](https://gitlab.slack.com/archives/C101F3796)
- [ ] Enable for gitlab-team-members: `/chatops gitlab run feature set --feature-group=gitlab_team_members work_items_autocomplete true`
- [ ] Verify that the feature works for internal users
### Global rollout on production
- [ ] Incrementally roll out the feature: `/chatops gitlab run feature set work_items_autocomplete 10 --actors`
- [ ] Monitor for 15 minutes, then increase to 25%
- [ ] Monitor for 15 minutes, then increase to 50%
- [ ] Monitor for 15 minutes, then increase to 100%
- [ ] After 100% for at least one day, proceed to cleanup
## Cleanup
See [Feature Flag Cleanup](https://gitlab.com/gitlab-org/gitlab/-/blob/master/.gitlab/issue_templates/Feature%20Flag%20Cleanup.md) template.
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