Add esbuild production bundle and multi-stage slim Docker image.

Bundle server (and mcp entry) into a single JS file with deps inlined, minify UI into one HTML, and ship only dist/ in the runtime image.

scripts/build.mjs

@@ -0,0 +1,105 @@
+#!/usr/bin/env node
+/**
+ * Production build: one Node bundle (all deps inlined) + minified single-file Web UI.
+ *
+ * Outputs:
+ *   dist/server.js   — main app (Torznab, qBt, MCP, UI API)
+ *   dist/mcp.js      — optional MCP-only process
+ *   dist/ui/index.html — Search/Queue UI (CSS+JS inlined)
+ */
+import * as esbuild from 'esbuild';
+import fs from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+const dist = path.join(root, 'dist');
+const distUi = path.join(dist, 'ui');
+
+fs.rmSync(dist, { recursive: true, force: true });
+fs.mkdirSync(distUi, { recursive: true });
+
+const nodeBundle = {
+  bundle: true,
+  platform: 'node',
+  target: 'node20',
+  format: 'cjs',
+  minify: true,
+  legalComments: 'none',
+  sourcemap: false,
+  // Keep Node builtins external; pull npm deps into the file.
+  packages: 'bundle',
+};
+
+async function bundleServer() {
+  const result = await esbuild.build({
+    ...nodeBundle,
+    entryPoints: [path.join(root, 'src/index.js')],
+    outfile: path.join(dist, 'server.js'),
+    metafile: true,
+    logLevel: 'info',
+  });
+  const out = result.metafile.outputs[Object.keys(result.metafile.outputs)[0]];
+  console.log(`server.js  ${(out.bytes / 1024 / 1024).toFixed(2)} MB`);
+}
+
+async function bundleMcp() {
+  const result = await esbuild.build({
+    ...nodeBundle,
+    entryPoints: [path.join(root, 'src/mcp.js')],
+    outfile: path.join(dist, 'mcp.js'),
+    banner: { js: '#!/usr/bin/env node\n' },
+    metafile: true,
+    logLevel: 'info',
+  });
+  const out = result.metafile.outputs[Object.keys(result.metafile.outputs)[0]];
+  console.log(`mcp.js     ${(out.bytes / 1024 / 1024).toFixed(2)} MB`);
+  try {
+    fs.chmodSync(path.join(dist, 'mcp.js'), 0o755);
+  } catch {
+    /* windows */
+  }
+}
+
+async function bundleUi() {
+  const cssSrc = fs.readFileSync(path.join(root, 'ui/styles.css'), 'utf8');
+  const jsSrc = fs.readFileSync(path.join(root, 'ui/scripts.js'), 'utf8');
+  const htmlSrc = fs.readFileSync(path.join(root, 'ui/index.html'), 'utf8');
+
+  const css = await esbuild.transform(cssSrc, { loader: 'css', minify: true });
+  const js = await esbuild.transform(jsSrc, {
+    loader: 'js',
+    minify: true,
+    target: ['es2020'],
+  });
+
+  // Prefer a single HTML payload (no extra static requests) for the tiny UI.
+  let html = htmlSrc
+    .replace(/<link rel="stylesheet" href="styles\.css">\s*/i, '')
+    .replace(/<script src="scripts\.js"><\/script>\s*/i, '');
+
+  // Inject minified assets before </head> and </body>
+  if (!html.includes('</head>')) {
+    throw new Error('ui/index.html missing </head>');
+  }
+  html = html.replace(
+    '</head>',
+    `<style>${css.code}</style>\n</head>`,
+  );
+  if (!html.includes('</body>')) {
+    throw new Error('ui/index.html missing </body>');
+  }
+  html = html.replace(
+    '</body>',
+    `<script>${js.code}</script>\n</body>`,
+  );
+
+  const outHtml = path.join(distUi, 'index.html');
+  fs.writeFileSync(outHtml, html);
+  console.log(`ui/index.html  ${(Buffer.byteLength(html) / 1024).toFixed(1)} KB (inlined css+js)`);
+}
+
+await bundleServer();
+await bundleMcp();
+await bundleUi();
+console.log('build ok → dist/');