docs: Update caveats for React cache documentation

Clarify cache behavior and limitations in React.

Author: aloeugene

src/content/reference/react/cache.md

@@ -64,6 +64,7 @@ The optimization of caching return values based on inputs is known as [_memoizat
 
 - React will invalidate the cache for all memoized functions for each server request.
 - Each call to `cache` creates a new function. This means that calling `cache` with the same function multiple times will return different memoized functions that do not share the same cache.
+- React uses shallow comparison (`Object.is`) for arguments. Passing a new object or array on every call will bypass the cache.
 - `cachedFn` will also cache errors. If `fn` throws an error for certain arguments, it will be cached, and the same error is re-thrown when `cachedFn` is called with those same arguments.
 - `cache` is for use in [Server Components](/reference/rsc/server-components) only.