feat: Add automated profit withdrawal system

- UI page: /withdrawals with stats dashboard and config form
- Settings API: GET/POST for .env configuration
- Stats API: Real-time profit and withdrawal calculations
- Execute API: Safe withdrawal with Drift SDK integration
- Drift service: withdrawFromDrift() with USDC spot market (index 0)
- Safety checks: Min withdrawal amount, min account balance, profit-only
- Telegram notifications: Withdrawal alerts with Solscan links
- Dashboard navigation: Added Withdrawals card (3-card grid)

User goal: 10% of profits automatically withdrawn on schedule
Current: Manual trigger ready, scheduled automation pending
Files: 5 new (withdrawals page, 3 APIs, Drift service), 2 modified

app/page.tsx

@@ -43,7 +43,7 @@ export default function HomePage() {
         </div>
 
         {/* Navigation Cards */}
-        <div className="grid md:grid-cols-2 gap-8 max-w-4xl mx-auto">
+        <div className="grid md:grid-cols-3 gap-8 max-w-6xl mx-auto">
           {/* Analytics Card */}
           <a
             href="/analytics"
@@ -71,6 +71,33 @@ export default function HomePage() {
             </div>
           </a>
 
+          {/* Withdrawals Card */}
+          <a
+            href="/withdrawals"
+            className="group relative bg-gradient-to-br from-emerald-900/50 to-teal-900/50 backdrop-blur-sm rounded-2xl p-8 border border-emerald-500/20 hover:border-emerald-500/40 transition-all duration-300 hover:scale-105"
+          >
+            <div className="absolute inset-0 bg-gradient-to-br from-emerald-500/10 to-teal-500/10 rounded-2xl opacity-0 group-hover:opacity-100 transition-opacity"></div>
+            
+            <div className="relative">
+              <div className="w-16 h-16 bg-gradient-to-br from-emerald-500 to-teal-600 rounded-xl flex items-center justify-center mb-6 group-hover:scale-110 transition-transform">
+                <span className="text-4xl">💸</span>
+              </div>
+              
+              <h3 className="text-2xl font-bold text-white mb-3">Withdrawals</h3>
+              
+              <p className="text-gray-300 mb-6">
+                Configure automatic profit withdrawals to your wallet
+              </p>
+              
+              <div className="flex items-center text-emerald-400 group-hover:text-emerald-300">
+                <span className="font-medium">Manage Withdrawals</span>
+                <svg className="w-5 h-5 ml-2 group-hover:translate-x-1 transition-transform" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                  <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
+                </svg>
+              </div>
+            </div>
+          </a>
+
           {/* Settings Card */}
           <a
             href="/settings"