fix(composer): include transaction processing errors in debug logging (#6)

Move `addSwapTransactions()` call inside the try/catch block in
`execute()` so that errors during transaction processing (such as
"Failed to process swap transaction at index X") are logged with
comprehensive failure context via `logSwapExecutionFailure()` before
being re-thrown to the developer's code.

Previously, only errors from `atc.execute()` received debug logging,
making it harder to diagnose intermittent transaction processing issues.

Author: drichar

packages/haystack/src/composer.ts

@@ -453,12 +453,12 @@ export class SwapComposer {
     txIds: string[]
     methodResults: ABIResult[]
   }> {
-    // Auto-add swap transactions if needed (maintains backward compatibility)
-    if (!this.swapTransactionsAdded) {
-      await this.addSwapTransactions()
-    }
-
     try {
+      // Auto-add swap transactions if needed (maintains backward compatibility)
+      if (!this.swapTransactionsAdded) {
+        await this.addSwapTransactions()
+      }
+
       const { txIDs, ...result } = await this.atc.execute(
         this.algodClient,
         waitRounds,