[QUESTION] How can we implement exponentialBackoff in the ADK (reusing or not the retry mechanism in `js-genai`)?

Hello,

When we use [js-genai](https://github.com/googleapis/js-genai/tree/b6c5d189bc0ae98550c45333c5e7a9bc43648dd3) directly, outside ADK, we can apply [httpOptions](https://github.com/googleapis/js-genai/blob/b6c5d189bc0ae98550c45333c5e7a9bc43648dd3/src/types.ts#L2020) to [modify](https://github.com/googleapis/js-genai/blob/b6c5d189bc0ae98550c45333c5e7a9bc43648dd3/src/types.ts#L1996C1-L2000C2) the default retry attempts. Since this is often not enough and one cannot modify the [default retry codes](https://github.com/googleapis/js-genai/blob/b6c5d189bc0ae98550c45333c5e7a9bc43648dd3/src/_api_client.ts#L48C7-L48C38), in our apps on production we wrap e.g., `chatSession.chat.sendMessage` with our own exponentialBackoff functionality. It covers other cases, like and error which just prints `fetch failed` too.

Now, we would like to apply the same, but how can we do this in the ADK? From what we see, ADK abstracts away the direct SDK calls, so we cannot easily wrap individual SDK invocations, can we?

One option was to extend Gemini's [*generateContentAsync](https://github.com/google/adk-js/blob/e8b2caeb219de7d84e1a9e399a52fe19cb9c70c9/core/src/models/google_llm.ts#L132C18-L132C39) method, but that seems like too much, doesn't it?

Note:
For the record, it seems Python guys allowed to [modify](https://github.com/google/adk-python/issues/1214#issuecomment-3144496751) the http retry options, but I'm not sure about implementing a custom exponential backoff logic.

Thanks,
Iliyan