tidy build config and deps

strip ollama proxy from vite, add deployment html injection plugin,
bump zxing dep for barcode scanning, ignore deploy artifacts

vite.config.ts

@@ -1,44 +1,37 @@
+import { existsSync, readFileSync } from "node:fs";
 import react from "@vitejs/plugin-react";
-import { defineConfig, loadEnv } from "vite";
+import type { Plugin } from "vite";
+import { defineConfig } from "vite";
 
-export default defineConfig(({ mode }) => {
-  const env = loadEnv(mode, process.cwd(), "");
-  const ollamaProxy = {
-    target: "https://ollama.com",
-    changeOrigin: true,
-    rewrite: () => "/api/chat",
-    configure(proxy: { on: (event: "proxyReq", handler: (proxyReq: { setHeader: (name: string, value: string) => void }) => void) => void }) {
-      proxy.on("proxyReq", (proxyReq) => {
-        if (env.OLLAMA_API_KEY) {
-          proxyReq.setHeader("Authorization", `Bearer ${env.OLLAMA_API_KEY}`);
-        }
-      });
-    },
-  };
-
-  return {
-    plugins: [react()],
-    server: {
-      proxy: {
-        "/api/ollama-chat": ollamaProxy,
-      },
-    },
-    preview: {
-      proxy: {
-        "/api/ollama-chat": ollamaProxy,
-      },
-    },
-    build: {
-      chunkSizeWarningLimit: 700,
-      rollupOptions: {
-        output: {
-          manualChunks: {
-            charts: ["recharts"],
-            motion: ["framer-motion"],
-            icons: ["lucide-react"],
-          },
+export default defineConfig(({ command }) => ({
+  plugins: [react(), deploymentHtml(command === "build")],
+  build: {
+    chunkSizeWarningLimit: 700,
+    rollupOptions: {
+      output: {
+        manualChunks: {
+          charts: ["recharts"],
+          motion: ["framer-motion"],
+          icons: ["lucide-react"],
         },
       },
     },
+  },
+}));
+
+function deploymentHtml(enabled: boolean): Plugin {
+  return {
+    name: "deployment-html",
+    transformIndexHtml(html) {
+      if (!enabled) return html;
+      return html
+        .replace("</head>", `${readOptional(".deploy/head.html")}</head>`)
+        .replace("</body>", `${readOptional(".deploy/body-end.html")}</body>`);
+    },
   };
-});
+}
+
+function readOptional(path: string) {
+  if (!existsSync(path)) return "";
+  return `\n${readFileSync(path, "utf8").trim()}\n`;
+}