chore: air hot-reload + configurable backend port for dev proxy

web/vite.config.ts

@@ -2,12 +2,16 @@ import { defineConfig } from "vite";
 import preact from "@preact/preset-vite";
 import tailwindcss from "@tailwindcss/vite";
 
+// Бэк для дев-прокси выбирается портом, не правкой кода:
+// BACKEND_PORT=8081 pnpm dev -> прокси на вторую (рабочую/дев) копию.
+const apiTarget = `http://localhost:${process.env.BACKEND_PORT ?? 8080}`;
+
 export default defineConfig({
   plugins: [preact(), tailwindcss()],
   server: {
     proxy: {
       // Connect RPC calls in dev go straight to the Go server.
-      "/homelab.v1.HomelabService": "http://localhost:8080",
+      "/homelab.v1.HomelabService": apiTarget,
     },
   },
 });