useSearchParams setter discards first update when called twice

[yinonburgansky]

Describe the bug

When calling the setParams function from useSearchParams() twice in succession (synchronously), only the second call takes effect.
Additionally, the params proxy doesn't reflect the changes immediately after calling setParams.

Your Example Website or App

https://stackblitz.com/edit/github-g4uj2mjx-jikitf3w?file=src%2Froutes%2Findex.tsx

Steps to Reproduce the Bug or Issue

1. click increment a and b
2. only b has incremented and a has not.

Expected behavior

Both a and b parameters should be incremented.

Screenshots or Videos

No response

Platform

• OS: Linux
• Browser: Chrome
• Version: 0.15.4

Additional context

This has come up when trying to create a helper hook to set search params:

function createSearchParamSignal<T>(
  key: string,
  transform: (val: string | string[] | undefined) => T
) {
  const [params, setParams] = useSearchParams();
  const getter = () => transform(params[key]);
  const setter = (val: T) =>
    setParams({ key: String(val) }, { replace: true, scroll: false });
  return [getter, setter] as const;
}

It would be nice to have the search param behave like signals:

const [a, setA] = createSearchParamSignal("a", (v) => (Number(v) || 0));
const [b, setB] = createSearchParamSignal("b", (v) => (Number(v) || 0));