noctalia-plugin: bar widget, toolbar panel and tile, with Luau tests and a flake check

noctalia-plugin/translations/en.json

@@ -0,0 +1,8 @@
+{
+  "bar": { "tooltip": "Screenshot" },
+  "tile": { "label": "Screenshot" },
+  "panel": { "unavailable": "valw is not available" },
+  "mode": { "screen": "Screen", "region": "Region", "window": "Window", "zoom": "Zoom" },
+  "timer": { "label": "Timer", "off": "Off" },
+  "option": { "cursor": "Show cursor", "preview": "Show preview", "sound": "Play sound" }
+}