feat: Jahresbericht-PDF pro Volk/Stand

Neue PDF-Reports im Export-Modul: colony-annual-report (Durchsichten,
Behandlungen, Varroakontrollen, Schwarmkontrolle, Ernten eines Volkes fuer
ein Jahr) und apiary-annual-report (Voelker-Uebersicht + Ernten eines
Stands fuer ein Jahr). Jahr ist optional, faellt auf das aktuelle Jahr
zurueck.

Frontend: "Jahresbericht"-Button auf Volk- und Stand-Detailseite, laedt
das PDF ueber den bestehenden Blob-Download-Mechanismus herunter.

ApiCore-Backend/test/export.e2e-spec.ts

@@ -131,4 +131,47 @@ describe('Export (e2e)', () => {
       .set('Authorization', `Bearer ${beekeeperToken}`)
       .expect(400);
   });
+
+  it('rejects the colony annual report without a colonyId', () => {
+    return request(app.getHttpServer())
+      .get('/api/v1/export/colony-annual-report.pdf')
+      .set('Authorization', `Bearer ${beekeeperToken}`)
+      .expect(400);
+  });
+
+  it('rejects the colony annual report for an unknown colony', () => {
+    return request(app.getHttpServer())
+      .get('/api/v1/export/colony-annual-report.pdf?colonyId=does-not-exist')
+      .set('Authorization', `Bearer ${beekeeperToken}`)
+      .expect(404);
+  });
+
+  it('renders a colony annual report PDF', async () => {
+    const response = await request(app.getHttpServer())
+      .get(`/api/v1/export/colony-annual-report.pdf?colonyId=${colonyId}`)
+      .set('Authorization', `Bearer ${beekeeperToken}`)
+      .expect(200);
+    expect(response.headers['content-type']).toContain('application/pdf');
+    expect((response.body as Buffer).subarray(0, 4).toString('latin1')).toBe(
+      '%PDF',
+    );
+  });
+
+  it('rejects the apiary annual report without an apiaryId', () => {
+    return request(app.getHttpServer())
+      .get('/api/v1/export/apiary-annual-report.pdf')
+      .set('Authorization', `Bearer ${beekeeperToken}`)
+      .expect(400);
+  });
+
+  it('renders an apiary annual report PDF', async () => {
+    const response = await request(app.getHttpServer())
+      .get(`/api/v1/export/apiary-annual-report.pdf?apiaryId=${apiaryId}`)
+      .set('Authorization', `Bearer ${beekeeperToken}`)
+      .expect(200);
+    expect(response.headers['content-type']).toContain('application/pdf');
+    expect((response.body as Buffer).subarray(0, 4).toString('latin1')).toBe(
+      '%PDF',
+    );
+  });
 });