Add Zed extension to website

Author: EpicEric

duper_website/docs/.vitepress/config.mts

@@ -85,7 +85,10 @@ export default async () => {
             },
             {
               text: "Editor support",
-              items: [{ text: "Visual Studio Code", link: "/tools/vs-code" }],
+              items: [
+                { text: "Visual Studio Code", link: "/tools/vs-code" },
+                { text: "Zed", link: "/tools/zed" },
+              ],
             },
             {
               text: "Tools",

duper_website/docs/tools/zed.md

@@ -0,0 +1,15 @@
+# Zed support
+
+Duper is available as [an extension for Zed](https://zed.dev/extensions/duper), with syntax highlighting, full LSP support, validation, and auto-formatting.
+
+In order to enable formatting via the LSP, add the following entry to `settings.json`:
+
+```json
+{
+  "languages": {
+    "Duper": {
+      "formatter": "language_server"
+    }
+  }
+}
+```