catch post request variable evaluation errors

fix #2005

- display post request variable evaluation errors in a toast, each individual variable error on a new line
- display the response body (was previously replaced by the an error "Error invoking remote method 'send-http-request': ..."

packages/bruno-electron/src/ipc/network/index.js

@@ -395,6 +395,10 @@ const registerNetworkIpc = (mainWindow) => {
           collectionUid
         });
       }
+
+      if (result?.error) {
+        mainWindow.webContents.send('main:display-error', result.error);
+      }
     }
 
     // run post-response script

packages/bruno-js/src/runtime/vars-runtime.js

@@ -56,14 +56,27 @@ class VarsRuntime {
       ...bruContext
     };
 
+    const errors = new Map();
     _.each(enabledVars, (v) => {
-      const value = evaluateJsExpression(v.value, context);
-      bru.setVar(v.name, value);
+      try {
+        const value = evaluateJsExpression(v.value, context);
+        bru.setVar(v.name, value);
+      } catch (error) {
+        errors.set(v.name, error);
+      }
     });
 
+    let error = null;
+    if (errors.size > 0) {
+      // Format all errors as a single string to be displayed in a toast
+      const errorMessage = [...errors.entries()].map(([name, err]) => `${name}: ${err.message ?? err}`).join('\n');
+      error = `${errors.size} error${errors.size === 1 ? '' : 's'} in post response variables: \n${errorMessage}`;
+    }
+
     return {
       envVariables,
-      collectionVariables
+      collectionVariables,
+      error
     };
   }
 }