feat: add config download functionality

src/componets/FileChooser.tsx

@@ -1,9 +1,9 @@
 import { Env } from "../models/Env";
 import { ConfigReader } from "../models/ConfigReader";
 import { Config } from "../models/Config";
+import { ConfigBuilder } from "../builders/ConfigBuilder";
 
-
-export function FileChooser(props: { onSelected: (x: Config) => void }) {
+export function FileChooser(props: { onSelected: (x: Config) => void, config?: Config }) {
   async function handleFile(x: React.ChangeEvent<HTMLInputElement>) {
     let file = x.target.files![0];
 
@@ -23,11 +23,42 @@ export function FileChooser(props: { onSelected: (x: Config) => void }) {
     props.onSelected(cfg);
   }
 
+  function handleDownload() {
+    if (!props.config) {
+      alert("No configuration loaded");
+      return;
+    }
+
+    const xmlContent = ConfigBuilder.buildFullXml(props.config);
+    const filename = ConfigBuilder.generateFilename();
+    
+    // Create blob and download
+    const blob = new Blob([xmlContent], { type: "text/xml" });
+    const url = URL.createObjectURL(blob);
+    const link = document.createElement("a");
+    link.href = url;
+    link.download = filename;
+    document.body.appendChild(link);
+    link.click();
+    document.body.removeChild(link);
+    URL.revokeObjectURL(url);
+  }
+
   return (
     <>
       <div className="col-2">
         <button className="btn btn-primary" onClick={handleNew} >Create new</button>
       </div>
+      <div className="col-auto">
+        <button 
+          className="btn btn-success" 
+          onClick={handleDownload}
+          disabled={!props.config}
+          title="Download full config template"
+        >
+          ⬇ Download
+        </button>
+      </div>
       <div className="col-1">or</div>
 
       <div className="col">