maven: fix test mocks for CalendarEvents interface (verification)

- Add CalendarEvents method to recordingAPI in auth_test.go
- Add CalendarEvents method to fakeCore in handlers_test.go

Co-Authored-By: opencode <opencode@anthropic.com>

internal/config/helpers_test.go

@@ -17,4 +17,4 @@ func writeFile(t *testing.T, path, body string) error {
 		}
 	}
 	return os.WriteFile(path, []byte(body), 0o600)
-}
+}