Add manual salary entry

frontend/vite.config.ts

@@ -3,6 +3,11 @@ import react from "@vitejs/plugin-react-oxc";
 import tailwindcss from "@tailwindcss/vite";
 import path from "path";
 
+// Browser requests arrive at Vite, which then proxies them to the backend.
+// Locally the backend is published on the host; Docker Compose supplies the
+// service hostname instead (see docker-compose.yml).
+const backendUrl = process.env.BACKEND_URL ?? "http://localhost:8001";
+
 export default defineConfig({
   plugins: [react(), tailwindcss()],
   resolve: {
@@ -19,7 +24,7 @@ export default defineConfig({
       },
       // All other API calls → Python backend
       "/api": {
-        target: "http://localhost:8001",
+        target: backendUrl,
         changeOrigin: true,
       },
     },