1512edfb85
Four copies of the 40/60 head/tail algorithm with a near-identical notice (terminal_tool_result, mcp_tool_content, code_execution_tool, environments/base_output) collapse into tools/tool_output_truncate.py, so the ratio and the `... [<LABEL> TRUNCATED - N <unit> omitted out of T total] ...` marker are defined once. execute_code keeps byte mode + spill path and only shares the notice/split. Visible change: the terminal notice now uses thousands separators like the other three (`9,000 chars` not `9000 chars`). kanban_specify._truncate: comment claimed escape stripping the body never did; comment now says what the plain clamp is for.