fix(CQ-WEB-8): Add React.memo to performance-sensitive components

Wrap 7 list-item/card components with React.memo to prevent unnecessary
re-renders when parent components update but props remain unchanged:
- TaskItem (task lists)
- EventCard (calendar views)
- EntryCard (knowledge base)
- WorkspaceCard (workspace list)
- TeamCard (team list)
- DomainItem (domain list)
- ConnectionCard (federation connections)

All are pure components rendered inside .map() loops that depend solely
on their props for rendering output.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/components/team/TeamCard.tsx

@@ -1,3 +1,4 @@
+import React from "react";
 import type { Team } from "@mosaic/shared";
 import { Card, CardHeader, CardContent } from "@mosaic/ui";
 import Link from "next/link";
@@ -7,7 +8,10 @@ interface TeamCardProps {
   workspaceId: string;
 }
 
-export function TeamCard({ team, workspaceId }: TeamCardProps): React.JSX.Element {
+export const TeamCard = React.memo(function TeamCard({
+  team,
+  workspaceId,
+}: TeamCardProps): React.JSX.Element {
   return (
     <Link href={`/settings/workspaces/${workspaceId}/teams/${team.id}`}>
       <Card className="hover:shadow-lg transition-shadow cursor-pointer">
@@ -27,4 +31,4 @@ export function TeamCard({ team, workspaceId }: TeamCardProps): React.JSX.Elemen
       </Card>
     </Link>
   );
-}
+});