When a Bedrock model makes multiple parallel tool calls, the Converse API
requires all toolResult blocks to be sent in a single user message.
Previously each tool result created a separate user message, causing a
ValidationException.
This fix detects consecutive tool result messages and appends them to
the same user message, producing the expected structure:
Message 0: user (prompt)
Message 1: assistant (toolUse A, toolUse B)
Message 2: user (toolResult A, toolResult B) ← grouped
Fixes#4749
Co-Authored-By: João <joao@crewai.com>
b125e572c4