Fix hydration recovery crashes (#1062)

Author: tannerlinsley

package.json

@@ -131,7 +131,7 @@
     "@tanstack/devtools-vite": "^0.7.0",
     "@tanstack/react-devtools": "^0.10.5",
     "@tanstack/react-query-devtools": "^5.100.11",
-    "@tanstack/redact": "^0.0.18",
+    "@tanstack/redact": "^0.0.19",
     "@types/hast": "^3.0.4",
     "@types/node": "^25.5.0",
     "@types/pg": "^8.20.0",

pnpm-lock.yaml

@@ -145,7 +145,7 @@ export const useTheme = () => {
 // Reads from DOM on client (matches what head script set), empty on server
 const getHtmlClass = createIsomorphicFn()
   .server(() => '')
-  .client(() => document.documentElement.className)
+  .client(() => document.documentElement?.className ?? '')
 
 export function useHtmlClass(): string {
   return getHtmlClass()