[BACKEND] Initialize Go backend structure and dependencies (#23)

src/js/version.js

@@ -0,0 +1,7 @@
+/**
+ * Chat Switchboard - Version Configuration
+ * Single source of truth: VERSION file at repo root
+ * Injected by build.sh at build time
+ */
+const SWITCHBOARD_VERSION = '__VERSION__';
+const APP_NAME = 'Chat Switchboard';