fix(stammbaum): import chipLabel/otherName from shared relationshipLabels in PersonRelationshipsCard

Removes local duplicates of the switch-statement label logic already
exported from $lib/relationshipLabels.ts. Adds two direction-sensitive
tests proving the Elternteil-von / Kind-von branch is covered.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/routes/persons/[id]/PersonRelationshipsCard.svelte

@@ -1,6 +1,6 @@
 <script lang="ts">
 import { m } from '$lib/paraglide/messages.js';
-import { inferredRelationshipLabel } from '$lib/relationshipLabels';
+import { chipLabel, otherName, inferredRelationshipLabel } from '$lib/relationshipLabels';
 import type { components } from '$lib/generated/api';
 
 type RelationshipDTO = components['schemas']['RelationshipDTO'];
@@ -19,37 +19,9 @@ const topDerived = $derived(
 	inferredRelationships.filter((d) => !directOtherIds.has(d.person.id)).slice(0, 5)
 );
 
-function chipLabel(rel: RelationshipDTO): string {
-	const viewpointIsSubject = rel.personId === personId;
-	switch (rel.relationType) {
-		case 'PARENT_OF':
-			return viewpointIsSubject ? m.relation_parent_of() : m.relation_child_of();
-		case 'SPOUSE_OF':
-			return m.relation_spouse_of();
-		case 'SIBLING_OF':
-			return m.relation_sibling_of();
-		case 'FRIEND':
-			return m.relation_friend();
-		case 'COLLEAGUE':
-			return m.relation_colleague();
-		case 'EMPLOYER':
-			return m.relation_employer();
-		case 'DOCTOR':
-			return m.relation_doctor();
-		case 'NEIGHBOR':
-			return m.relation_neighbor();
-		default:
-			return m.relation_other();
-	}
-}
-
 function otherId(rel: RelationshipDTO): string {
 	return rel.personId === personId ? rel.relatedPersonId : rel.personId;
 }
-
-function otherName(rel: RelationshipDTO): string {
-	return rel.personId === personId ? rel.relatedPersonDisplayName : rel.personDisplayName;
-}
 </script>
 
 <div class="rounded-sm border border-line bg-surface p-6 shadow-sm">
@@ -67,13 +39,13 @@ function otherName(rel: RelationshipDTO): string {
 						<span
 							class="inline-flex shrink-0 items-center rounded-full border border-accent/40 bg-accent/15 px-2 py-0.5 font-sans text-[10px] font-bold tracking-widest text-ink uppercase"
 						>
-							{chipLabel(rel)}
+							{chipLabel(rel, personId)}
 						</span>
 						<a
 							href="/persons/{otherId(rel)}"
 							class="min-w-0 flex-1 truncate font-serif text-sm text-ink hover:underline"
 						>
-							{otherName(rel)}
+							{otherName(rel, personId)}
 						</a>
 					</li>
 				{/each}

frontend/src/routes/persons/[id]/PersonRelationshipsCard.svelte.test.ts

@@ -5,6 +5,7 @@ import PersonRelationshipsCard from './PersonRelationshipsCard.svelte';
 
 const PERSON_ID = '00000000-0000-0000-0000-000000000001';
 const SPOUSE_ID = '00000000-0000-0000-0000-000000000002';
+const PARENT_ID = '00000000-0000-0000-0000-000000000003';
 
 describe('PersonRelationshipsCard', () => {
 	it('hides an inferred relationship that is already a direct one', async () => {
@@ -53,4 +54,42 @@ describe('PersonRelationshipsCard', () => {
 
 		await expect.element(page.getByText('Carla Cousine')).toBeInTheDocument();
 	});
+
+	it('shows Elternteil-von chip when personId is the PARENT_OF subject', async () => {
+		render(PersonRelationshipsCard, {
+			personId: PERSON_ID,
+			relationships: [
+				{
+					id: 'r1',
+					personId: PERSON_ID,
+					relatedPersonId: PARENT_ID,
+					personDisplayName: 'Anna Müller',
+					relatedPersonDisplayName: 'Kind Müller',
+					relationType: 'PARENT_OF'
+				}
+			],
+			inferredRelationships: []
+		});
+
+		await expect.element(page.getByText('Elternteil von')).toBeInTheDocument();
+	});
+
+	it('shows Kind-von chip when personId is the PARENT_OF object', async () => {
+		render(PersonRelationshipsCard, {
+			personId: PERSON_ID,
+			relationships: [
+				{
+					id: 'r2',
+					personId: PARENT_ID,
+					relatedPersonId: PERSON_ID,
+					personDisplayName: 'Eltern Müller',
+					relatedPersonDisplayName: 'Anna Müller',
+					relationType: 'PARENT_OF'
+				}
+			],
+			inferredRelationships: []
+		});
+
+		await expect.element(page.getByText('Kind von')).toBeInTheDocument();
+	});
 });