Added E2E test for updating issue status to backlog in tests/e2e/test_inline_editing.py:264-301. The test follows the same pattern as existing status update tests (test_update_issue_status_to_in_progress and test_update_issue_status_to_todo): 1. Creates a test issue with todo status 2. Opens the inline status dropdown 3. Selects backlog status 4. Verifies the status icon updates in the UI 5. Verifies persistence via API All 8 tests in TestInlineStatusEditing pass. Merged to master and pushed to remote.