fix: SetTeam transaction now shows as system event in timeline

- Added SetTeam to isSystem check
- Shows 'Team changed' in the timeline instead of raw 'SetTeam' text

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/src/app/tickets/[id]/page.tsx

@@ -113,6 +113,7 @@ function TransactionCard({
   const isSystem =
     tx.transaction_type === "StatusChange" ||
     tx.transaction_type === "SetOwner" ||
+    tx.transaction_type === "SetTeam" ||
     tx.transaction_type === "CustomFieldChange" ||
     tx.transaction_type === "Create";
   const isInternal = tx.transaction_type === "Comment";
@@ -132,6 +133,8 @@ function TransactionCard({
       message = `Status changed from ${oldLabel} to ${newLabel}`;
     } else if (tx.transaction_type === "SetOwner") {
       message = tx.new_value ? `Assigned to ${userLabel(users, tx.new_value)}` : "Unassigned";
+    } else if (tx.transaction_type === "SetTeam") {
+      message = "Team changed";
     } else if (tx.transaction_type === "CustomFieldChange") {
       const fieldName = tx.field ? customFieldLabels[tx.field] ?? "Custom field" : "Custom field";
       message = tx.new_value ? `${fieldName} set to ${tx.new_value}` : `${fieldName} cleared`;