i18n: add upload-banner + enrichment-block keys

Singular/plural banner copy, a count-aware "show all" footer link, and
the dismiss aria-label for the new dashboard enrichment-list-block
(issue #296). Covers de / en / es.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/messages/de.json

@@ -415,6 +415,11 @@
 	"dashboard_notification_replied": "hat geantwortet",
 	"dashboard_needs_metadata_heading": "Metadaten fehlen",
 	"dashboard_needs_metadata_show_all": "Alle anzeigen",
+	"dashboard_needs_metadata_show_all_count": "Alle {count} anzeigen →",
+	"upload_banner_singular": "1 Dokument hochgeladen.",
+	"upload_banner_plural": "{count} Dokumente hochgeladen.",
+	"upload_banner_cta": "Jetzt ergänzen →",
+	"upload_banner_close": "Benachrichtigung schließen",
 	"dashboard_recent_heading": "Zuletzt aktiv",
 	"dashboard_stats_documents": "Dokumente",
 	"dashboard_stats_persons": "Personen",