feat(persons): extract personType + title in edit action; relax firstName for non-PERSON

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

frontend/src/routes/persons/[id]/edit/+page.server.ts

@@ -30,6 +30,12 @@ export async function load({ params, fetch, locals }) {
 export const actions = {
 	update: async ({ request, params, fetch }) => {
 		const formData = await request.formData();
+		const personType = (formData.get('personType')?.toString() ?? 'PERSON') as
+			| 'PERSON'
+			| 'INSTITUTION'
+			| 'GROUP'
+			| 'UNKNOWN';
+		const title = formData.get('title')?.toString().trim() || undefined;
 		const firstName = formData.get('firstName')?.toString().trim();
 		const lastName = formData.get('lastName')?.toString().trim();
 		const alias = formData.get('alias')?.toString().trim() || undefined;
@@ -39,15 +45,20 @@ export const actions = {
 		const birthYear = birthYearStr ? parseInt(birthYearStr, 10) : undefined;
 		const deathYear = deathYearStr ? parseInt(deathYearStr, 10) : undefined;
 
-		if (!firstName || !lastName) {
-			return fail(400, { updateError: 'Vor- und Nachname sind Pflichtfelder.' });
+		if (!lastName) {
+			return fail(400, { updateError: 'Nachname ist Pflichtfeld.' });
+		}
+		if (personType === 'PERSON' && !firstName) {
+			return fail(400, { updateError: 'Vorname ist Pflichtfeld.' });
 		}
 
 		const api = createApiClient(fetch);
 		const result = await api.PUT('/api/persons/{id}', {
 			params: { path: { id: params.id } },
 			body: {
-				firstName,
+				personType,
+				...(title ? { title } : {}),
+				...(firstName ? { firstName } : {}),
 				lastName,
 				...(alias ? { alias } : {}),
 				...(notes ? { notes } : {}),