feat: agent discovery (Link headers, markdown negotiation, Content-Signal)

- Add `Content-Signal: search=yes, ai-train=yes, ai-input=yes` to robots.txt
- Add `Link` response headers advertising `/api-reference/introduction` (service-doc) and `/sitemap.xml` (sitemap)
- Serve source markdown when `Accept: text/markdown` is sent — static `.md` files copied into `dist` by a VitePress `buildEnd` hook, routed via a Vercel `rewrites` header matcher

Author: sriramveeraghanta

docs/.vitepress/config.ts

@@ -1,5 +1,5 @@
-import { readFileSync } from "fs";
-import { resolve } from "path";
+import { copyFileSync, mkdirSync, readFileSync, readdirSync, statSync } from "fs";
+import { dirname, join, relative, resolve } from "path";
 import { defineConfig, type HeadConfig } from "vitepress";
 import { tabsMarkdownPlugin } from "vitepress-plugin-tabs";
 
@@ -50,6 +50,30 @@ export default defineConfig({
   description: "Modern project management software",
   cleanUrls: true,
 
+  buildEnd(siteConfig) {
+    // Copy source .md files into dist/ for Accept: text/markdown negotiation.
+    const srcDir = siteConfig.srcDir;
+    const outDir = siteConfig.outDir;
+
+    function walk(dir: string): void {
+      for (const entry of readdirSync(dir)) {
+        if (entry === ".vitepress" || entry === "public" || entry === "node_modules") continue;
+        const abs = join(dir, entry);
+        const stat = statSync(abs);
+        if (stat.isDirectory()) {
+          walk(abs);
+        } else if (stat.isFile() && abs.endsWith(".md")) {
+          const rel = relative(srcDir, abs);
+          const dest = join(outDir, rel);
+          mkdirSync(dirname(dest), { recursive: true });
+          copyFileSync(abs, dest);
+        }
+      }
+    }
+
+    walk(srcDir);
+  },
+
   head: [
     [
       "link",

docs/public/robots.txt

@@ -6,4 +6,8 @@ Disallow: /core-concepts/issues.html
 Disallow: /core-concepts/projects/run-project
 Disallow: /importers/github-imp
 
+# Content Signals — AI content usage preferences
+# https://contentsignals.org/
+Content-Signal: search=yes, ai-train=yes, ai-input=yes
+
 Sitemap: https://docs.plane.so/sitemap.xml

vercel.json

@@ -1,6 +1,17 @@
 {
   "cleanUrls": true,
   "trailingSlash": false,
+  "headers": [
+    {
+      "source": "/(.*)",
+      "headers": [
+        {
+          "key": "Link",
+          "value": "</api-reference/introduction>; rel=\"service-doc\"; type=\"text/html\", </sitemap.xml>; rel=\"sitemap\"; type=\"application/xml\""
+        }
+      ]
+    }
+  ],
   "redirects": [
     {
       "source": "/quick-start",
@@ -262,5 +273,12 @@
       "source": "/performance/hyper-mode",
       "destination": "/"
     }
+  ],
+  "rewrites": [
+    {
+      "source": "/:path*",
+      "has": [{ "type": "header", "key": "accept", "value": ".*text/markdown.*" }],
+      "destination": "/:path*.md"
+    }
   ]
 }