feat: docker & build

rsbuild.config.ts

@@ -2,7 +2,21 @@ import { defineConfig } from '@rsbuild/core';
 import { pluginBabel } from '@rsbuild/plugin-babel';
 import { pluginReact } from '@rsbuild/plugin-react';
 
+// In docker dev the container binds 0.0.0.0:3000 and the browser reaches it
+// through nginx on :80 — so HMR must be told the client-facing port. All three
+// vars are unset for a plain `npm run dev`, where the defaults apply.
+const { RSBUILD_HOST, RSBUILD_PORT, RSBUILD_HMR_CLIENT_PORT } = process.env;
+
 export default defineConfig({
+  server: {
+    host: RSBUILD_HOST ?? 'localhost',
+    port: RSBUILD_PORT ? Number(RSBUILD_PORT) : 3000,
+  },
+  dev: {
+    client: RSBUILD_HMR_CLIENT_PORT
+      ? { port: Number(RSBUILD_HMR_CLIENT_PORT) }
+      : undefined,
+  },
   plugins: [
     pluginReact(),
     pluginBabel({