feat: zap the winner button with lightning animation

Add ZAP WINNER button in FightViewer after fight ends. Server endpoint
POST /api/payments/zap increments zapsReceived on winner bot. Show zap
count on bot profile page. Add zaps_received column with migration.

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

server/src/db/startup.ts

@@ -102,6 +102,8 @@ export function runMigrations() {
     "ALTER TABLE bots ADD COLUMN sats_won INTEGER NOT NULL DEFAULT 0",
     "ALTER TABLE bots ADD COLUMN sats_wagered INTEGER NOT NULL DEFAULT 0",
     "ALTER TABLE bots ADD COLUMN has_wallet INTEGER NOT NULL DEFAULT 0",
+    // Zap tracking
+    "ALTER TABLE bots ADD COLUMN zaps_received INTEGER NOT NULL DEFAULT 0",
     // Classic bots
     "ALTER TABLE bots ADD COLUMN bot_type TEXT NOT NULL DEFAULT 'regular'",
   ]