ATLAS-5260: ATLAS UI: [UI] Detail page – terms from entity header, labels/UDP save fixes (dashboard + dashboardv2)

[pawarprasad123]

What changes were proposed in this pull request?

Entity detail relied on relationshipAttributes.meanings, which is empty when the detail API is called with ignoreRelationships=true. We enrich terms from the entity header API when appropriate, and align label/UDP behavior with the classic UI.

Scope
React UI (dashboard/)

After loading detail, call GET /v2/entity/guid/{guid}/header when relationshipAttributes.meanings is missing/empty and the entity is not AtlasGlossary*.
Map header term assignments to the shape expected by chips/remove-term (guid, relationshipGuid, etc.).
-Labels: normalize save payload to string[], allow saving an empty list to clear all labels, use explicit POST for /labels.
-User-defined properties: omit blank keys from payload; on Cancel, reset form to current server values (not a single empty row only).

-Classic UI (dashboardv2/)
When meanings are missing on the main entity response, fetch the same entity header and merge meanings, then render terms and update the Backbone model.

Technical notes
Detail GET continues to use ignoreRelationships=true for performance; header GET is the lightweight term supplement.
Optional: mention unrelated build fix if this ticket includes the whole branch — export getLatestEntities in searchApiMethod.ts for DashboardOverview (TypeScript compile).

Acceptance criteria
on-glossary entity with assigned terms shows terms in the header after load (React).
Same behavior on classic detail page when meanings were empty on main GET.
Glossary entity types do not show/require the terms strip in line with existing UX.
Labels: add, edit, and remove all labels persist after refresh.

• UDP: save ignores rows with empty keys; Cancel restores the last loaded properties.

How was this patch tested?

Manually tested, Build passed