feat: integrate vitepress-plugin-llms for llms.txt generation

Replaces the custom buildEnd walk that copied raw source .md into dist
with vitepress-plugin-llms, which emits llms.txt, llms-full.txt, and
per-page cleaned markdown. Agents hitting /path.md via Accept:
text/markdown now get LLM-friendly output without frontmatter layout
directives or Vue component markup.

Author: sriramveeraghanta

docs/.vitepress/config.mts

@@ -1,8 +1,9 @@
 import { defineConfig, type HeadConfig } from "vitepress";
 import { tabsMarkdownPlugin } from "vitepress-plugin-tabs";
 import { withMermaid } from "vitepress-plugin-mermaid";
-import { readFileSync, readdirSync, statSync, mkdirSync, copyFileSync } from "node:fs";
-import { resolve, join, relative, dirname } from "node:path";
+import llmstxt from "vitepress-plugin-llms";
+import { readFileSync } from "node:fs";
+import { resolve } from "node:path";
 
 function loadEnvVar(key: string): string | undefined {
   // process.env takes precedence (CI/hosting platforms set vars here)
@@ -59,6 +60,7 @@ export default withMermaid(
       // Mermaid configuration options
     },
     vite: {
+      plugins: [llmstxt()],
       optimizeDeps: {
         include: [
           "lucide-vue-next",
@@ -75,29 +77,6 @@ export default withMermaid(
         ],
       },
     },
-    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);
-    },
     title: "Plane developer documentation",
     description:
       "Self-host Plane, integrate with our API, configure webhooks, and extend your project management platform. Complete guides for developers building on Plane.",

package.json

@@ -25,6 +25,7 @@
     "prettier": "^3.8.1",
     "tailwindcss": "^4.1.18",
     "vitepress": "^1.6.4",
+    "vitepress-plugin-llms": "^1.12.1",
     "vitepress-plugin-mermaid": "^2.0.17",
     "vitepress-plugin-tabs": "^0.7.3",
     "vue": "^3.5.26"