feat: read-only external attendees strip on applicant dashboard

Adds lunch.getProjectExternals (team-member guarded). Strip auto-hides
when no externals attached to the team.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/applicant/external-attendees-strip.tsx

@@ -0,0 +1,25 @@
+'use client'
+
+import { trpc } from '@/lib/trpc/client'
+import { Card, CardContent } from '@/components/ui/card'
+import { Badge } from '@/components/ui/badge'
+import { UsersRound } from 'lucide-react'
+
+export function ExternalAttendeesStrip({ projectId }: { projectId: string }) {
+  const { data } = trpc.lunch.getProjectExternals.useQuery({ projectId })
+  if (!data || data.length === 0) return null
+  return (
+    <Card>
+      <CardContent className="flex flex-wrap items-center gap-2 py-3">
+        <UsersRound className="text-muted-foreground h-4 w-4" />
+        <span className="text-sm font-medium">External attendees joining your team:</span>
+        {data.map((e) => (
+          <Badge key={e.id} variant="outline">
+            {e.name}
+            {e.roleNote ? ` (${e.roleNote})` : ''}
+          </Badge>
+        ))}
+      </CardContent>
+    </Card>
+  )
+}