Fix 12145 - Ledger errors being set as `Error: [object, object]` (#12176)

* Fixes #12145

When transactions fail, preserve error message when presented with an error object. Fallback to stringified error for other cases.

* Perserve error stack when err.stack is present, else set stack to message.

* Use optional chaining

app/scripts/controllers/transactions/tx-state-manager.js

@@ -521,7 +521,7 @@ export default class TransactionStateManager extends EventEmitter {
 
     const txMeta = this.getTransaction(txId);
     txMeta.err = {
-      message: error.toString(),
+      message: error.message?.toString() || error.toString(),
       rpc: error.value,
       stack: error.stack,
     };

app/scripts/lib/cleanErrorStack.js

@@ -14,7 +14,7 @@ export default function cleanErrorStack(err) {
     err.stack = err.message;
   } else if (msg === '') {
     err.stack = err.name;
-  } else {
+  } else if (!err.stack) {
     err.stack = `${err.name}: ${err.message}`;
   }