test(bulk-upload): add positive navigation assertion for successful save

The error-path test (goto not called on failure) had no matching positive
assertion. Added: save() navigates to /documents when all chunks succeed.

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

frontend/src/lib/components/document/BulkDocumentEditLayout.svelte.spec.ts

@@ -140,6 +140,25 @@ describe('BulkDocumentEditLayout', () => {
 		expect(metadataJson).toHaveProperty('tagNames');
 	});
 
+	it('save() navigates to /documents when all chunks succeed', async () => {
+		const mockFetch = vi.fn().mockResolvedValue({
+			ok: true,
+			json: async () => ({ created: [], updated: [], errors: [] })
+		});
+		vi.stubGlobal('fetch', mockFetch);
+
+		const { container } = render(BulkDocumentEditLayout, {});
+		await addFilesViaInput(container, [makeFile('doc.pdf')]);
+
+		const saveBtn = container.querySelector(
+			'button[data-testid="bulk-save-btn"]'
+		) as HTMLButtonElement;
+		saveBtn.click();
+
+		await vi.waitFor(() => expect(mockFetch).toHaveBeenCalledTimes(1), { timeout: 3000 });
+		await vi.waitFor(() => expect(goto).toHaveBeenCalledWith('/documents'), { timeout: 3000 });
+	});
+
 	it('save() does not navigate when chunk returns non-ok response', async () => {
 		const mockFetch = vi.fn().mockResolvedValue({
 			ok: false,