fix(hover-card): use orientation-aware relationship labels; allow spaces in mention

PersonHoverCard was showing the hovered person as their own parent when stored
as the object side of a PARENT_OF row — now uses chipLabel/otherName from
relationshipLabels (same helpers the person detail page uses) to resolve the
correct name and label from the caller's perspective.

PersonMentionEditor: add allowSpaces:true so typing a last name after a space
no longer exits mention mode mid-query.

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

frontend/src/lib/components/PersonHoverCard.svelte.spec.ts

@@ -165,6 +165,31 @@ describe('PersonHoverCard — loaded state', () => {
 		await expect.element(friendChip).not.toBeInTheDocument();
 	});
 
+	it('shows the other person name when hovered person is the object (relatedPersonId) in a PARENT_OF row', async () => {
+		// Storage: Heinrich PARENT_OF Auguste. When viewing Auguste's card,
+		// the chip must show "Heinrich" (the parent), not "Auguste" (herself).
+		const relationships: RelationshipDTO[] = [
+			{
+				id: 'r-parent',
+				personId: 'p-heinrich',
+				relatedPersonId: 'p-aug',
+				personDisplayName: 'Heinrich Raddatz',
+				relatedPersonDisplayName: 'Auguste Raddatz',
+				relationType: 'PARENT_OF'
+			}
+		];
+		render(PersonHoverCard, {
+			personId: 'p-aug',
+			cardId: 'card-1',
+			position: POSITION,
+			state: { status: 'loaded', person: AUGUSTE, relationships }
+		});
+		await expect.element(page.getByText('Heinrich Raddatz')).toBeInTheDocument();
+		// Auguste must NOT appear as her own parent chip name
+		const chips = document.querySelector('[data-testid="person-hover-card-chips"]');
+		expect(chips?.textContent).not.toContain('Auguste Raddatz');
+	});
+
 	it('omits the chips section entirely when no family relationships', async () => {
 		const onlyFriend: RelationshipDTO[] = [
 			{