Heredoc bodies and interpreter inline scripts (python3 - <<'EOF', cat > file.rs <<'EOF', node -e '...') are split from the shell text and highlighted in their own language. The language comes from the interpreter behind wrappers such as uv run or timeout, the cat/tee target extension, or the heredoc delimiter. Long bodies collapse to 10 lines until expanded. PowerShell calls are unchanged.
Streaming highlight caching is shared with the write renderer: growing text only highlights new lines plus a bounded prefix, is fully highlighted once when the arguments complete, and is reused for output updates until the theme changes.
