✨(version) convey version information to the /config endpoint and footer

We add the machinery to get version information and display it discreetly.

src/frontend/apps/desk/version.json

@@ -0,0 +1,6 @@
+{
+    "source":"people",
+    "version":"version",
+    "commit":"commit",
+    "build": "NA"
+}