ref(core): Add more specific exception mechanism for internal errors (#17253)

see #17212 
part of #17252

Author: Lms24

packages/core/src/client.ts

@@ -1160,6 +1160,10 @@ export abstract class Client<O extends ClientOptions = ClientOptions> {
         }
 
         this.captureException(reason, {
+          mechanism: {
+            handled: false,
+            type: 'internal',
+          },
           data: {
             __sentry__: true,
           },

packages/core/test/lib/client.test.ts

@@ -1848,12 +1848,17 @@ describe('Client', () => {
 
       client.captureEvent({ message: 'hello' }, {}, scope);
 
-      expect(TestClient.instance!.event!.exception!.values![0]).toStrictEqual({ type: 'Error', value: 'sorry' });
+      expect(TestClient.instance!.event!.exception!.values![0]).toStrictEqual({
+        type: 'Error',
+        value: 'sorry',
+        mechanism: { type: 'internal', handled: false },
+      });
       expect(captureExceptionSpy).toBeCalledWith(exception, {
         data: {
           __sentry__: true,
         },
         originalException: exception,
+        mechanism: { type: 'internal', handled: false },
       });
       expect(loggerWarnSpy).toBeCalledWith(
         `Event processing pipeline threw an error, original event will not be sent. Details have been sent as a new event.\nReason: ${exception}`,