fix: label swap methods as "Swap" in tx lists, remove unused variable

- Map known DEX methods (execute, swap, multicall, etc.) to "Swap"
  label instead of showing raw method name like "Execute"
- Remove unused displayData variable in transactionDetail.js

src/shared/transactions.js

@@ -37,7 +37,16 @@ function parseTx(tx, addrLower) {
         if (token) {
             symbol = token.symbol;
         }
-        const label = method.charAt(0).toUpperCase() + method.slice(1);
+        // Map known DEX methods to "Swap" for cleaner display
+        const SWAP_METHODS = new Set([
+            "execute", "swap", "swapExactTokensForTokens",
+            "swapTokensForExactTokens", "swapExactETHForTokens",
+            "swapTokensForExactETH", "swapExactTokensForETH",
+            "swapETHForExactTokens", "multicall",
+        ]);
+        const label = SWAP_METHODS.has(method)
+            ? "Swap"
+            : method.charAt(0).toUpperCase() + method.slice(1);
         direction = "contract";
         directionLabel = label;
         value = "";