fix(deps): pin @vue/server-renderer to vue via overrides

Renovate's vue-monorepo group only bumps direct deps. @vue/server-renderer
is pulled transitively via @vue/test-utils and has an exact-pin peer on vue,
so vue minor bumps fail ERESOLVE and the artifact lockfile update fails.

Using npm overrides with $vue keeps @vue/server-renderer in lockstep with
vue automatically. Lockfile regenerated inside node:24-bookworm-slim so the
Linux-side optional-dep graph (@emnapi/core, @emnapi/runtime, etc.) is
preserved for the CI build.

package.json

@@ -60,5 +60,8 @@
     "typescript-eslint": "8.59.3",
     "vitest": "4.1.6",
     "vue-eslint-parser": "10.4.0"
+  },
+  "overrides": {
+    "@vue/server-renderer": "$vue"
   }
 }