fix: correct Mailgun API URL and enhance error handling in MailgunAccount class

- Fixed the incorrect API URL in MailgunAccount class.
- Improved error handling for email sending failures by providing detailed error messages based on response content.
- Updated test file to export the tap.start() function for better module integration.

package.json

@@ -9,17 +9,17 @@
   "author": "Lossless GmbH",
   "license": "MIT",
   "scripts": {
-    "test": "(tstest test/)",
+    "test": "(tstest test/ --verbose)",
     "build": "(tsbuild --web --allowimplicitany)",
     "format": "(gitzone format)",
     "buildDocs": "tsdoc"
   },
   "devDependencies": {
     "@git.zone/tsbuild": "^2.1.65",
-    "@git.zone/tstest": "^2.5.0",
+    "@git.zone/tstest": "^2.6.1",
     "@push.rocks/qenv": "^6.1.3",
     "@push.rocks/tapbundle": "^6.0.3",
-    "@types/node": "^24.7.2"
+    "@types/node": "^22.0.0"
   },
   "dependencies": {
     "@push.rocks/smartfile": "^11.2.7",

test/test.ts

@@ -66,4 +66,4 @@ tap.test('should retrieve a mail using a retrieval url', async () => {
   }
 });
 
-tap.start();
+export default tap.start();

ts/mailgun.classes.account.ts

@@ -18,7 +18,7 @@ export class MailgunAccount {
     this.apiBaseUrl =
       this.options.region === 'eu'
         ? 'https://api.eu.mailgun.net/v3'
-        : 'https://api..mailgun.net/v3';
+        : 'https://api.mailgun.net/v3';
   }
 
   /**
@@ -127,8 +127,24 @@ export class MailgunAccount {
         );
         return await response.json();
       } else {
-        console.log(await response.json());
+        let errorMessage = `HTTP ${response.status}: ${response.statusText}`;
-        throw new Error('could not send email');
+        try {
+          // Get response body as text first
+          const errorText = await response.text();
+          console.log(errorText);
+
+          // Try to parse as JSON
+          try {
+            const errorBody = JSON.parse(errorText);
+            errorMessage = errorBody.message || JSON.stringify(errorBody);
+          } catch {
+            // Not JSON, use plain text
+            errorMessage = errorText || errorMessage;
+          }
+        } catch {
+          // Couldn't read body at all
+        }
+        throw new Error(`could not send email: ${errorMessage}`);
       }
     } else {
       console.log(