fix(search): tagQ alone now triggers search mode; selecting chip clears tagQ

- isDashboard was ignoring tagQ so typing in tag filter showed dashboard
- addTag now calls onTextInput('') to clear tagQ when a chip is selected

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

frontend/src/lib/components/TagInput.svelte

@@ -44,6 +44,7 @@ function addTag(tag: string) {
 	suggestions = [];
 	showSuggestions = false;
 	activeIndex = -1;
+	onTextInput?.('');
 }
 
 function removeTag(index: number) {

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

@@ -228,4 +228,16 @@ describe('TagInput – onTextInput callback', () => {
 		const input = page.getByRole('textbox');
 		await expect(input.fill('fa')).resolves.not.toThrow();
 	});
+
+	it('calls onTextInput with empty string when a tag chip is added', async () => {
+		mockFetchWithTags(['Kaufvertrag']);
+		const onTextInput = vi.fn();
+		render(TagInput, { tags: [], allowCreation: false, onTextInput });
+		const input = page.getByRole('textbox');
+		await input.fill('Ka');
+		await waitForDebounce();
+		const option = page.getByRole('option', { name: 'Kaufvertrag' });
+		await option.click();
+		await expect.poll(() => onTextInput.mock.calls.at(-1)).toEqual(['']);
+	});
 });

frontend/src/routes/+page.server.ts

@@ -17,7 +17,7 @@ export async function load({ url, fetch }) {
 	const dir = url.searchParams.get('dir') || 'desc';
 	const tagQ = url.searchParams.get('tagQ') || '';
 
-	const isDashboard = !q && !from && !to && !senderId && !receiverId && !tags.length;
+	const isDashboard = !q && !from && !to && !senderId && !receiverId && !tags.length && !tagQ;
 
 	const api = createApiClient(fetch);
 

frontend/src/routes/page.server.spec.ts

@@ -167,6 +167,27 @@ describe('home page load — search mode', () => {
 		expect(firstCall[1].params.query.q).toBe('Urlaub');
 		expect(firstCall[1].params.query.from).toBe('2020-01-01');
 	});
+
+	it('sets isDashboard false when only tagQ is set', async () => {
+		const mockGet = vi
+			.fn()
+			.mockResolvedValueOnce({
+				response: { ok: true, status: 200 },
+				data: { documents: [{ id: 'd1' }], total: 1 }
+			}) // search docs
+			.mockResolvedValueOnce({ response: { ok: true, status: 200 }, data: [] }); // persons
+		vi.mocked(createApiClient).mockReturnValue({ GET: mockGet } as ReturnType<
+			typeof createApiClient
+		>);
+
+		const result = await load({
+			url: makeUrl({ tagQ: 'fam' }),
+			fetch: vi.fn() as unknown as typeof fetch
+		});
+
+		expect(result.isDashboard).toBe(false);
+		expect(result.documents).toHaveLength(1);
+	});
 });
 
 it('passes sort, dir, and tagQ params to the documents API', async () => {