Resolves#36976
- [X] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
## Testing
- [X] Added/updated automated tests
- [X] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Label operations (create, edit, delete) now generate activities shown
in the activity feed with label and optional fleet context.
* Host label add/remove operations emit corresponding label edited
activities; duplicate label names are deduplicated.
* Label activity types are selectable/filterable in the activity
dashboard.
* **Tests**
* Added unit, integration, and UI tests covering label activity
emission, rendering, filtering, and GitOps label lifecycle scenarios.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->