daeb683528
- Added `prepareToolCallDispatch` and `PreparedToolCall` to handle argument validation and `beforeToolCall` before message snapshotting. - Implemented `preparedDispatchByMessage` WeakMap to store pre-dispatch results for streamed messages. - Updated `executeToolCalls` to consume pre-computed dispatch preparation results. - Updated documentation and changelog to specify `beforeToolCall` timing on the streamed path.