Display frontend / backend version at the homescreen

bookie/src/environments/environment.prod.ts

@@ -1,4 +1,5 @@
 export const environment = {
   production: true,
   ACCESS_TOKEN_REFRESH_MINUTES: 10, // refresh token 10 minutes before expiry
+  version: "1.0.0",
 };

bookie/src/environments/environment.ts

@@ -5,6 +5,7 @@
 export const environment = {
   production: false,
   ACCESS_TOKEN_REFRESH_MINUTES: 10, // refresh token 10 minutes before expiry
+  version: "1.0.0",
 };
 
 /*