feat(persons): redesign detail page sections to match Concept A spec

- CoCorrespondentsList: white card wrapper with navy initials circles in chips
- PersonDocumentList: flat row-divider pattern with variant-tinted icons (sent=navy, received=teal)
- Add variant prop (sent/received) to PersonDocumentList and wire up in page
- Add person_correspondents_hint i18n key to all three message files

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

frontend/messages/de.json

@@ -120,6 +120,7 @@
 	"person_role_sender": "Gesendet",
 	"person_role_receiver": "Empfangen",
 	"person_co_correspondents_heading": "Häufige Korrespondenten",
+	"person_correspondents_hint": "klicken für Konversation",
 	"person_show_more": "+ {count} weitere anzeigen",
 	"conv_heading": "Konversationen",
 	"conv_subtitle": "Verfolgen Sie den Schriftverkehr zwischen zwei Personen chronologisch.",

frontend/messages/en.json

@@ -120,6 +120,7 @@
 	"person_role_sender": "Sent",
 	"person_role_receiver": "Received",
 	"person_co_correspondents_heading": "Frequent correspondents",
+	"person_correspondents_hint": "click to view conversation",
 	"person_show_more": "+ {count} more",
 	"conv_heading": "Conversations",
 	"conv_subtitle": "Follow the correspondence between two persons chronologically.",

frontend/messages/es.json

@@ -120,6 +120,7 @@
 	"person_role_sender": "Enviado",
 	"person_role_receiver": "Recibido",
 	"person_co_correspondents_heading": "Corresponsales frecuentes",
+	"person_correspondents_hint": "clic para ver conversación",
 	"person_show_more": "+ {count} más",
 	"conv_heading": "Conversaciones",
 	"conv_subtitle": "Siga la correspondencia entre dos personas cronológicamente.",