Add FounderHQ to v0

NEXT_PUBLIC_FOUNDERHQ_KEY = fhq_pk_XXXX

Add FounderHQ analytics to this project.

1. Install the package @founderhq/events.

2. Read the key from process.env.NEXT_PUBLIC_FOUNDERHQ_KEY. Do not paste
   the key value into any file. If the project is not Next.js, rename the
   variable to the prefix my build tool needs and tell me the new name.

3. Detect the project shape, then pick one placement:
   - Next.js App Router: create a client component that calls
     founderhq.init(key) inside a useEffect with an empty dependency array
     and returns null. Render that component once in app/layout.tsx.
   - A plain React app: call founderhq.init(key) once at the app's entry
     point, at module scope.
   Pick one placement only. Never initialize it twice.

4. Only if this app already has sign-in: after a successful sign-in, call
   founderhq.identify with the user's stable database id, and their email
   as a property. Call founderhq.reset() on sign-out. If the app has no
   sign-in, skip this step. Do not add authentication.

5. Do not add any other analytics tool. Do not change analytics tools that
   are already installed.

End state: the app renders one FounderHQ initializer, founderhq.init runs
once with the key from the environment, and pageviews are captured without
any further code.

"use client";

import { useEffect } from "react";
import { founderhq } from "@founderhq/events";

export function FounderHqAnalytics() {
  useEffect(() => {
    founderhq.init(process.env.NEXT_PUBLIC_FOUNDERHQ_KEY!);
  }, []);
  return null;
}