Add Amount update

Author: jessealama

2026/09.md

@@ -113,6 +113,7 @@ When applicable, use these emoji as a prefix to the agenda item topic.
     | stage | timebox | topic | presenter |
     |:-----:|:-------:|-------|-----------|
     | 3 | 5m | [Iterator Join](https://github.com/tc39/proposal-iterator-join) for Stage 4 ([PR](https://github.com/tc39/ecma262/pull/3948), [implementation status](https://github.com/tc39/proposal-iterator-join/issues/7)) | Kevin Gibbons |
+    | 2 | 30m | [Amount](https://github.com/tc39/proposal-amount/) Stage 2 Update (slides TBA) | Jesse Alama |
     | 1 | 60m | [Composites](https://github.com/tc39/proposal-composites) for Stage 2 ([draft spec](https://tc39.es/proposal-composites/), [slides](https://docs.google.com/presentation/d/1lN-LdmUQ9Nh6bF-5uuuuAQhHtDBTmI9xfYyj6TH_8F4/)) | Ashley Claymore |
 
 1. Longer or open-ended discussions