fix(docs): make link-check a cached task that depends on gen:docs

The docs link-check previously ran as a package.json script:
  vp run -w gen && node validate-links.mjs

Script caching (cache.scripts) only caches stdout; it does not archive
or restore files produced by a script. The generated example pages live
under docs/content/examples/** (written by the dev-scripts gen:docs
task), so on a cache-replay of the gen script those files were not
restored, and validate-links raced ahead reading a stale/empty
content/examples dir -> '13 errors / not-found' for every /examples link.

Define docs#test as a Vite Task that dependsOn @blocknote/dev-scripts#gen:docs
instead. Task output archiving restores docs/content/examples/** on a
cache hit, and the task graph guarantees gen:docs fully completes before
validation runs. Verified locally: deleting the generated dirs and
re-running 'vp run test' restores the files on cache hit and reports
'0 errored file, 0 errors'.

Author: nperez0111

docs/package.json

@@ -12,8 +12,7 @@
     "types:check": "fumadocs-mdx && next typegen && tsc --noEmit",
     "postinstall": "fumadocs-mdx",
     "lint": "vp lint",
-    "init-db": "pnpx @better-auth/cli migrate",
-    "test": "vp run -w gen && node validate-links.mjs"
+    "init-db": "pnpx @better-auth/cli migrate"
   },
   "dependencies": {
     "@ai-sdk/groq": "^3.0.2",

docs/vite.config.ts

@@ -0,0 +1,22 @@
+import { defineConfig } from "vite-plus";
+
+export default defineConfig({
+  run: {
+    tasks: {
+      // Validate that all `/examples/...` (and other) links referenced in the
+      // docs resolve to a real page. The example pages under
+      // `content/examples/**` are generated by the dev-scripts `gen:docs`
+      // task, so we depend on it here. Declaring the dependency as a task
+      // (instead of chaining `vp run gen && node validate-links.mjs` as a
+      // package.json script) lets Vite Task's caching archive & restore the
+      // generated files: on a cache hit the example pages are restored before
+      // this task runs, and on a fresh run the dependency fully completes
+      // before validation starts. This avoids a race where validate-links ran
+      // before `gen:docs` finished writing `docs/content/examples/**`.
+      test: {
+        command: "node validate-links.mjs",
+        dependsOn: ["@blocknote/dev-scripts#gen:docs"],
+      },
+    },
+  },
+});