feat: add exit animations on lead cards and cross-page filter continuity

- Wrap lead cards in AnimatePresence/motion.div so they fade+slide out when removed from the NEW filter
- Update "View All" link to pass active source filter as ?source= URL param
- Initialize AllLeadsPage sourceFilter from URL search params on mount

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

src/pages/all-leads.tsx

@@ -1,4 +1,5 @@
 import { useMemo, useState } from 'react';
+import { useSearchParams } from 'react-router';
 import { ArrowLeft, Download01, FilterLines, SearchLg, SwitchVertical01 } from '@untitledui/icons';
 import { Button } from '@/components/base/buttons/button';
 import { Input } from '@/components/base/input/input';
@@ -29,11 +30,13 @@ const PAGE_SIZE = 25;
 
 export const AllLeadsPage = () => {
     const { user } = useAuth();
+    const [searchParams] = useSearchParams();
+    const initialSource = searchParams.get('source') as LeadSource | null;
     const [tab, setTab] = useState<TabKey>('new');
     const [selectedIds, setSelectedIds] = useState<string[]>([]);
     const [sortField, setSortField] = useState('createdAt');
     const [sortDirection, setSortDirection] = useState<'asc' | 'desc'>('desc');
-    const [sourceFilter, setSourceFilter] = useState<LeadSource | null>(null);
+    const [sourceFilter, setSourceFilter] = useState<LeadSource | null>(initialSource);
     const [searchQuery, setSearchQuery] = useState('');
     const [currentPage, setCurrentPage] = useState(1);