fix: fix endless recursion during dts generation

[HerrCai0907]

Fix #2269

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[MaxGraey]

What about this approach?

let isPlain = this.isPlainObject(clazz);
typeName = `${isPlain ? "__Record" : "__Internref"}${clazz.id}`;
sb.push(typeName);
seenObjectTypes.set(clazz, typeName);
if (isPlain) {
  sb.push(mode == Mode.EXPORT ? "<never>" : "<undefined>");
  this.deferredTypings.push(this.makeRecordType(clazz, mode));
} else {
  this.deferredTypings.push(this.makeInternrefType(clazz));
}

[MaxGraey]

Thanks!