fix(transcribe): localise Delete key cap + annotation label, clarify Esc row (#327)

Review follow-up (Leonie, Requirements Engineer): the Delete key cap was a
hardcoded German "Entf" shown to EN/ES users — now driven by key_cap_delete
(Entf/Del/Supr). The annotation read-only aria-label was a hardcoded German
"Block anzeigen" in all locales — now annotation_view_label. Renamed the Esc
row label from "Bereich schließen" to "Panel schließen" so it no longer
collides with "Bereich" (= region) used elsewhere in the cheatsheet.

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

frontend/messages/de.json

@@ -936,12 +936,14 @@
 	"shortcut_new_region": "Neuen Bereich zeichnen",
 	"shortcut_toggle_training": "Für Training markieren",
 	"shortcut_delete_region": "Aktuellen Bereich löschen",
-	"shortcut_close_panel": "Bereich schließen",
+	"shortcut_close_panel": "Panel schließen",
 	"shortcut_help": "Tastaturkürzel anzeigen",
 	"shortcut_draw_hint": "Ziehen Sie mit der Maus einen Bereich auf.",
+	"key_cap_delete": "Entf",
 	"cheatsheet_title": "Tastaturkürzel",
 	"cheatsheet_close": "Kürzelübersicht schließen",
 	"cheatsheet_autosave_hint": "Änderungen werden automatisch gespeichert.",
+	"annotation_view_label": "Block anzeigen",
 	"annotation_label_with_delete": "Block anzeigen, Entf zum Löschen.",
 	"transcription_mode_help_label": "Lese- und Bearbeitungsmodus",
 	"transcription_mode_help_body": "Lesen zeigt die Transkription als fließenden Text. Bearbeiten öffnet die Textfelder für jede Passage.",

frontend/messages/en.json

@@ -939,9 +939,11 @@
 	"shortcut_close_panel": "Close panel",
 	"shortcut_help": "Show keyboard shortcuts",
 	"shortcut_draw_hint": "Drag a region with your mouse.",
+	"key_cap_delete": "Del",
 	"cheatsheet_title": "Keyboard shortcuts",
 	"cheatsheet_close": "Close shortcut overview",
 	"cheatsheet_autosave_hint": "Changes are saved automatically.",
+	"annotation_view_label": "View block",
 	"annotation_label_with_delete": "Show block, press Delete to remove.",
 	"transcription_mode_help_label": "Read and edit mode",
 	"transcription_mode_help_body": "Read shows the transcription as flowing text. Edit opens the text fields for each passage.",

frontend/messages/es.json

@@ -939,9 +939,11 @@
 	"shortcut_close_panel": "Cerrar panel",
 	"shortcut_help": "Mostrar atajos de teclado",
 	"shortcut_draw_hint": "Arrastre una región con el ratón.",
+	"key_cap_delete": "Supr",
 	"cheatsheet_title": "Atajos de teclado",
 	"cheatsheet_close": "Cerrar el resumen de atajos",
 	"cheatsheet_autosave_hint": "Los cambios se guardan automáticamente.",
+	"annotation_view_label": "Ver bloque",
 	"annotation_label_with_delete": "Mostrar bloque, pulse Supr para eliminar.",
 	"transcription_mode_help_label": "Modo lectura y edición",
 	"transcription_mode_help_body": "Lectura muestra la transcripción como texto continuo. Edición abre los campos de texto para cada pasaje.",