Issue: Streaming tool calls crash on special characters due to premature JSON repair

Issue: Streaming tool calls crash on special characters due to premature JSON repair: a task in LegoFlow-SWE (Harbor dataset). Description: When using streaming chat models with tool calling, the system attempts to parse and repair incomplete JSON from intermediate streaming chunks. This becomes…

The task

**Description:** When using streaming chat models with tool calling, the system attempts to parse and repair incomplete JSON from intermediate streaming chunks. This becomes problematic when tool call parameters contain special characters (e.g., newlines, quotes, backslashes, or truncated content) that produce…

Part of Lego-X/LegoFlow-SWE.