Add Renewal Timeline visualization to Account Explorer

Collapsible SVG timeline showing Next Renewal and Anchor Contract dates
for all filtered accounts. Color-coded account names by opportunity status
(green=won/late stage, yellow=early stage, black=lost, gray=none). Includes
dollar amount slider filter, Today marker, and year/quarter gridlines.

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

src/app/(dashboard)/accounts/page.tsx

@@ -12,6 +12,7 @@ import { ExportButton } from '@/components/ui/ExportButton';
 import { scoreAccountHealth, HEALTH_LEVEL_COLORS } from '@/lib/scoring';
 import { AccountNotes } from '@/components/account/AccountNotes';
 import { ContactMap } from '@/components/account/ContactMap';
+import { RenewalTimeline } from '@/components/ui/RenewalTimeline';
 import {
   BarChart, Bar, XAxis, YAxis, Tooltip, ResponsiveContainer, Cell,
 } from 'recharts';
@@ -546,6 +547,9 @@ export default function AccountExplorer() {
         </ChartCard>
       </div>
 
+      {/* Renewal Timeline */}
+      <RenewalTimeline accounts={filteredAccounts} pipeline={pipeline} />
+
       {/* Search & Filters */}
       <div className="flex flex-wrap gap-2 mb-2">
         <input