chore: Add messages from the keyboard experiment. (#8904)

* chore: Add messages from the keyboard experiment.

* fix: Resolve duplicate message ID.

* fix: Use placeholders for keyboard shortcuts.

msg/json/en.json

@@ -1,7 +1,7 @@
 {
 	"@metadata": {
 		"author": "Ellen Spertus <ellen.spertus@gmail.com>",
-		"lastupdated": "2024-04-16 23:19:53.668551",
+		"lastupdated": "2025-04-21 08:25:34.842680",
 		"locale": "en",
 		"messagedocumentation" : "qqq"
 	},
@@ -396,5 +396,34 @@
 	"WORKSPACE_ARIA_LABEL": "Blockly Workspace",
 	"COLLAPSED_WARNINGS_WARNING": "Collapsed blocks contain warnings.",
 	"DIALOG_OK": "OK",
-	"DIALOG_CANCEL": "Cancel"
+	"DIALOG_CANCEL": "Cancel",
+	"DELETE_SHORTCUT": "Delete block (%1)",
+	"DELETE_KEY": "Del",
+	"EDIT_BLOCK_CONTENTS": "Edit Block contents (%1)",
+	"INSERT_BLOCK": "Insert Block (%1)",
+	"START_MOVE": "Start move",
+	"FINISH_MOVE": "Finish move",
+	"ABORT_MOVE": "Abort move",
+	"MOVE_LEFT_CONSTRAINED": "Move left, constrained",
+	"MOVE_RIGHT_CONSTRAINED": "Move right constrained",
+	"MOVE_UP_CONSTRAINED": "Move up, constrained",
+	"MOVE_DOWN_CONSTRAINED": "Move down constrained",
+	"MOVE_LEFT_UNCONSTRAINED": "Move left, unconstrained",
+	"MOVE_RIGHT_UNCONSTRAINED": "Move right, unconstrained",
+	"MOVE_UP_UNCONSTRAINED": "Move up unconstrained",
+	"MOVE_DOWN_UNCONSTRAINED": "Move down, unconstrained",
+	"MOVE_BLOCK": "Move Block (%1)",
+	"WINDOWS": "Windows",
+	"MAC_OS": "macOS",
+	"CHROME_OS": "ChromeOS",
+	"LINUX": "Linux",
+	"UNKNOWN": "Unknown",
+	"CONTROL_KEY": "Ctrl",
+	"COMMAND_KEY": "⌘ Command",
+	"OPTION_KEY": "⌥ Option",
+	"ALT_KEY": "Alt",
+	"CUT_SHORTCUT": "Cut (%1)",
+	"COPY_SHORTCUT": "Copy (%1)",
+	"PASTE_SHORTCUT": "Paste (%1)",
+	"HELP_PROMPT": "Press %1 for help on keyboard controls"
 }