feat(geschichten): chip-row UI for multi-person AND filter

The /geschichten list page now renders one removable chip per active
person filter and lets users add more via the existing typeahead. The
URL uses repeated ?personId= params (matching the documents tag
filter), which the regenerated API client passes straight through to
the backend's new array-bound endpoint. New translation keys cover the
chip remove aria-label, the AND hint shown while picking, and the
multi-person empty state.

frontend/messages/de.json

@@ -929,7 +929,10 @@
 	"geschichten_filter_all_pill": "Alle",
 	"geschichten_filter_choose_person": "Person wählen",
 	"geschichten_filter_aria_label": "Person filtern",
+	"geschichten_filter_remove_chip": "{name} aus Filter entfernen",
+	"geschichten_filter_and_hint": "Es werden nur Geschichten gezeigt, in denen alle ausgewählten Personen vorkommen.",
 	"geschichten_empty_for_person": "Keine Geschichten für {name} gefunden.",
+	"geschichten_empty_for_persons": "Keine Geschichten für {names} gefunden.",
 	"geschichten_empty_no_filter": "Es gibt noch keine veröffentlichten Geschichten.",
 	"geschichten_back_to_index": "Zurück zu Geschichten",
 	"geschichten_published_on": "veröffentlicht am {date}",

frontend/messages/en.json

@@ -929,7 +929,10 @@
 	"geschichten_filter_all_pill": "All",
 	"geschichten_filter_choose_person": "Choose person",
 	"geschichten_filter_aria_label": "Filter by person",
+	"geschichten_filter_remove_chip": "Remove {name} from filter",
+	"geschichten_filter_and_hint": "Only stories that include every selected person are shown.",
 	"geschichten_empty_for_person": "No stories found for {name}.",
+	"geschichten_empty_for_persons": "No stories found for {names}.",
 	"geschichten_empty_no_filter": "There are no published stories yet.",
 	"geschichten_back_to_index": "Back to stories",
 	"geschichten_published_on": "published on {date}",

frontend/messages/es.json

@@ -929,7 +929,10 @@
 	"geschichten_filter_all_pill": "Todas",
 	"geschichten_filter_choose_person": "Elegir persona",
 	"geschichten_filter_aria_label": "Filtrar por persona",
+	"geschichten_filter_remove_chip": "Quitar {name} del filtro",
+	"geschichten_filter_and_hint": "Solo se muestran las historias que incluyen a todas las personas seleccionadas.",
 	"geschichten_empty_for_person": "No hay historias para {name}.",
+	"geschichten_empty_for_persons": "No hay historias para {names}.",
 	"geschichten_empty_no_filter": "Aún no hay historias publicadas.",
 	"geschichten_back_to_index": "Volver a Historias",
 	"geschichten_published_on": "publicada el {date}",