feat(documents): rebalance list row — summary + archive chips, restored sender/receiver

Refill the columns that went visually empty after the previous dedup
commit (`fc0fc57`):

- Middle column gains the document `summary` (line-clamp-2, italic,
  with `summaryOffsets` highlighting — the backend already populates
  the offsets, the frontend just wasn't rendering them) and a row of
  thin neutral chips for `archiveBox`, `archiveFolder`, and `location`
  (~99% of docs in the corpus carry these). Chips are desktop-only
  and skip empty values.
- Right column restores `VON sender` and `AN receivers`, now with
  `<mark>` highlighting that the previous right-column copy lacked,
  so search matches stay visible there.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

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

@@ -118,28 +118,99 @@ describe('DocumentRow – sender', () => {
 		await expect.element(unknownElements.first()).toBeInTheDocument();
 	});
 
-	it('renders the sender display name only once across the row', async () => {
+	it('highlights the sender when senderMatched is true', async () => {
 		const item = makeItem({
 			document: {
 				...makeItem().document,
 				sender: { id: 's1', displayName: 'Großmutter Maria' }
+			},
+			matchData: {
+				...makeItem().matchData,
+				senderMatched: true
 			}
 		});
 		render(DocumentRow, { item });
-		const matches = await page.getByText('Großmutter Maria').all();
-		expect(matches.length).toBe(1);
+		const mark = page.getByRole('mark').first();
+		await expect.element(mark).toHaveTextContent('Großmutter Maria');
 	});
 
-	it('renders each receiver display name only once across the row', async () => {
+	it('highlights a receiver when matchedReceiverIds includes its id', async () => {
 		const item = makeItem({
 			document: {
 				...makeItem().document,
 				receivers: [{ id: 'r1', displayName: 'Onkel Karl' }]
+			},
+			matchData: {
+				...makeItem().matchData,
+				matchedReceiverIds: ['r1']
 			}
 		});
 		render(DocumentRow, { item });
-		const matches = await page.getByText('Onkel Karl').all();
-		expect(matches.length).toBe(1);
+		const mark = page.getByRole('mark').first();
+		await expect.element(mark).toHaveTextContent('Onkel Karl');
+	});
+});
+
+// ─── Summary ─────────────────────────────────────────────────────────────────
+
+describe('DocumentRow – summary', () => {
+	it('renders the document summary when present', async () => {
+		const item = makeItem({
+			document: {
+				...makeItem().document,
+				summary: 'Brief von Eugenie über die Heimreise aus dem Süden.'
+			}
+		});
+		render(DocumentRow, { item });
+		await expect
+			.element(page.getByTestId('doc-summary'))
+			.toHaveTextContent('Brief von Eugenie über die Heimreise aus dem Süden.');
+	});
+
+	it('does not render the summary block when summary is empty', async () => {
+		render(DocumentRow, { item: makeItem() });
+		await expect.element(page.getByTestId('doc-summary')).not.toBeInTheDocument();
+	});
+
+	it('applies summary search-match highlight via summaryOffsets', async () => {
+		const item = makeItem({
+			document: { ...makeItem().document, summary: 'Brief über Menton' },
+			matchData: {
+				...makeItem().matchData,
+				summaryOffsets: [{ start: 11, length: 6 }]
+			}
+		});
+		render(DocumentRow, { item });
+		const mark = page.getByRole('mark').first();
+		await expect.element(mark).toHaveTextContent('Menton');
+	});
+});
+
+// ─── Archive chips ───────────────────────────────────────────────────────────
+
+describe('DocumentRow – archive chips', () => {
+	it('renders the archive box chip when set', async () => {
+		const item = makeItem({
+			document: { ...makeItem().document, archiveBox: 'K3' }
+		});
+		render(DocumentRow, { item });
+		await expect.element(page.getByText('K3')).toBeInTheDocument();
+	});
+
+	it('renders the archive folder chip when set', async () => {
+		const item = makeItem({
+			document: { ...makeItem().document, archiveFolder: 'Mappe A' }
+		});
+		render(DocumentRow, { item });
+		await expect.element(page.getByText('Mappe A')).toBeInTheDocument();
+	});
+
+	it('renders the location chip when meta_location is set', async () => {
+		const item = makeItem({
+			document: { ...makeItem().document, location: 'Berlin' }
+		});
+		render(DocumentRow, { item });
+		await expect.element(page.getByText('Berlin')).toBeInTheDocument();
 	});
 });