Add Timeline test for monitored authors

Add ui/src/components/dashboard/Timeline.test.tsx to verify Timeline falls back to monitored_authors when proposition details lack raw authorship. The test renders the component with a sample DashboardActivityPropositionOut and asserts the monitored author's name, party and state are displayed using vitest and React Testing Library.

Author: fmercurio

ui/src/components/dashboard/Timeline.test.tsx

@@ -0,0 +1,44 @@
+import { render, screen } from '@testing-library/react';
+import { describe, expect, it } from 'vitest';
+
+import type { DashboardActivityPropositionOut } from '@/api/types';
+import { Timeline } from './Timeline';
+
+describe('Timeline', () => {
+  it('uses monitored authors when proposition details do not expose raw authorship', () => {
+    const camaraAmendment: DashboardActivityPropositionOut = {
+      id: 48475,
+      proposition_code: 2624861,
+      title: 'EMC 1/2026',
+      link: 'https://www.camara.leg.br/proposicoesWeb/fichadetramitacao?idProposicao=2624861',
+      proposition_acronym: 'EMC',
+      proposition_number: 1,
+      presentation_year: 2026,
+      agency_id: null,
+      proposition_type_id: null,
+      proposition_status_id: null,
+      current_status: 'Apresentação do REQ n. 3131/2026',
+      proposition_description: 'Emenda à PEC',
+      presentation_date: '2026-05-14',
+      presentation_month: 5,
+      summary: null,
+      details: {},
+      created_at: '2026-05-14T00:00:00',
+      updated_at: '2026-05-14T00:00:00',
+      monitored_authors: [
+        {
+          id: 86,
+          name: 'Adilson Barroso',
+          full_name: 'ADILSON BARROSO OLIVEIRA',
+          party: 'PL',
+          state_elected: 'SP',
+          type: 'Deputado',
+        },
+      ],
+    };
+
+    render(<Timeline propositions={[camaraAmendment]} votes={[]} />);
+
+    expect(screen.getByText('Adilson Barroso PL - SP')).toBeInTheDocument();
+  });
+});