fix(scope): all pages react to company scope change via useScopeEffect

- Created useScopeEffect hook that auto-triggers reload on scope change
- Replaced useEffect([], []) with useScopeEffect in 20+ pages
- Risks/Reports/Dashboard also use useScopeEffect
- Removed redundant per-page useCompanyScope where only effect was needed

frontend/src/app/(investor)/customer-success/page.tsx

@@ -1,6 +1,7 @@
 "use client";
 
-import { useEffect, useState } from "react";
+import { useState } from "react";
+import { useScopeEffect } from "@/lib/company-scope";
 import { apiFetch } from "@/lib/api";
 import { LoadingSpinner } from "@/components/shared/LoadingSpinner";
 import { EmptyState } from "@/components/shared/EmptyState";
@@ -50,10 +51,10 @@ export default function CustomerSuccessPage() {
     }
   }
 
-  useEffect(() => {
+  useScopeEffect(() => {
     // eslint-disable-next-line react-hooks/set-state-in-effect
     loadChurnRisks();
-  }, []);
+  });
 
   async function handleQBR() {
     if (!qbrData.trim()) return;