Function format_connection_error 

pub fn format_connection_error(error: &Error) -> String

Render the full context chain of a connection-related anyhow::Error.

This uses anyhow’s alternate Display form ({:#}), which walks the entire error chain and joins each layer with ": ", e.g. "outer context: middle context: root cause". This mirrors the format already used by the parallel exec path (src/executor/parallel.rs), so interactive-mode and exec-mode terminal output stay visually consistent.