fix: wire role-based views — sidebar auth, user display, table tabs, card actions

- Sidebar: use useAuth() for isAdmin and pass auth user to NavAccountCard
- NavAccountCard: fix bug where items prop was ignored (used placeholderAccounts)
- TopBar: replace hardcoded "SM" initials with user.initials from auth
- All Leads: add "My Leads" tab filtering by assignedAgent matching user
- Lead Card: add role-aware action buttons (Call/Disposition for assigned leads)
- Lead Workspace: pass onLogCall/onUpdateStatus handlers to LeadCard

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/components/application/app-navigation/base-components/nav-account-card.tsx

@@ -167,7 +167,7 @@ export const NavAccountCard = ({
     const triggerRef = useRef<HTMLDivElement>(null);
     const isDesktop = useBreakpoint("lg");
 
-    const selectedAccount = placeholderAccounts.find((account) => account.id === selectedAccountId);
+    const selectedAccount = items.find((account) => account.id === selectedAccountId);
 
     if (!selectedAccount) {
         console.warn(`Account with ID ${selectedAccountId} not found in <NavAccountCard />`);