🏷️(app-desk) add custom-next.d.ts file

Add custom-next.d.ts file to augment types.
We add our environment variables to avoid mispelling
and to have better autocompletion.

src/frontend/apps/desk/tsconfig.json

@@ -22,6 +22,12 @@
       "@/*": ["./src/*"]
     }
   },
-  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts"],
+  "include": [
+    "src/custom-next.d.ts",
+    "next-env.d.ts",
+    "**/*.ts",
+    "**/*.tsx",
+    ".next/types/**/*.ts"
+  ],
   "exclude": ["node_modules"]
 }