Emojis in work item titles are not rendered in the work item detail page
## Summary
Emoji shortcodes (e.g. `:rocket:`) and copy-pasted emojis in work item titles are not rendered in several areas of the work item detail page. This is a follow-up to https://gitlab.com/gitlab-org/gitlab/-/work_items/14572, which tracks the same problem in the issues list view.
## Areas affected
The following locations on the work item detail page currently display raw emoji shortcodes instead of rendered emojis:
- **Ancestry widget** — the breadcrumb-style ancestor chain displayed above the title when parent/ancestor work items exist
- **Child items** — titles of child work items listed in the hierarchy widget
- **Linked items** — titles of related/blocking/blocked-by work items in the linked items widget
- **Parent field (sidebar)** — the parent work item title shown in the sidebar
- **Work item reference popovers** — the title shown when hovering over a work item reference link
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## Expected behavior
Emoji shortcodes in work item titles should be rendered as emoji glyphs consistently across all areas of the work item detail page, matching the behavior already implemented for the title itself (via `titleHtml`).
## Notes
- The fix for the detail view title was implemented via https://gitlab.com/gitlab-org/gitlab/-/merge_requests/184070 and https://gitlab.com/gitlab-org/gitlab/-/merge_requests/224839.
- The correct approach is to use `titleHtml` (the pre-rendered HTML version of the title) wherever a work item title is displayed, rather than the raw `title` field.
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