fix(deploy): fix Vercel deployments by upgrading Node and adding config (#1011)

* fix(deploy): fix Vercel deployments by upgrading Node and adding config

Vercel dropped Node 14 support, causing all Production and Preview
deployments to fail. Upgrades website engine to Node 18 and adds
vercel.json to explicitly configure the docs site build.

Closes #1006

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(deploy): move vercel.json to website/ and use Node 24

Moves vercel.json into website/ so Vercel reads the website's
package.json engines field instead of the root (which is for the
library). Sets Node engine to 24.x per Vercel deployment logs.

Requires setting Root Directory to "website/" in Vercel project
settings.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(deploy): add openssl-legacy-provider for Node 24 compatibility

VuePress 1.x's cache-loader uses md4 hashing which OpenSSL 3.0
(bundled with Node 24) rejects. Adding --openssl-legacy-provider
as suggested by Vercel's build logs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ctrlplusb

website/package.json

@@ -1,12 +1,11 @@
 {
   "private": true,
   "engines": {
-    "node": "14.x"
+    "node": "24.x"
   },
   "scripts": {
     "dev": "vuepress dev docs",
-    "build": "vuepress build docs",
-    "deploy": "vercel --prod"
+    "build": "vuepress build docs"
   },
   "devDependencies": {
     "@vuepress/plugin-google-analytics": "^1.9.9",

website/vercel.json

@@ -0,0 +1,5 @@
+{
+  "buildCommand": "NODE_OPTIONS=--openssl-legacy-provider yarn build",
+  "outputDirectory": "docs/.vuepress/dist",
+  "framework": null
+}