add always visible lock icon on top right to show info about e… (#1403)

* improvement(layerui.js): add lock icon on top right to show encrypted info about excalidraw

fixes https://github.com/excalidraw/excalidraw/issues/1313

* swap lock with shield

* fix dimensions

* make link open in new tab

* add newline between toolip text and link

* increase tooltip line-height

* remove unused GitHubCorner compo

* reposition; reintroduce GH icon

* make shield into link

* make tooltip not show when drawing

* Review fix

* remove link from tooltip

Co-authored-by: dwelle <luzar.david@gmail.com>

src/locales/en.json

@@ -151,5 +151,8 @@
     "github": "Found an issue? Submit",
     "textNewLine": "Add new line (text)",
     "textFinish": "Finish editing (text)"
+  },
+  "encrypted": {
+    "tooltip": "Your drawings are end-to-end encrypted so Excalidraw's servers will never see them.\nClick the icon to learn more..."
   }
 }