Leak-free runner backed by forcola.
Every claude invocation runs under forcola's Rust shim, which places
the CLI in its own process group and kills the whole group (SIGTERM,
then SIGKILL) on timeout, on early stream halt, or when the BEAM dies.
That reaps claude and every stdio MCP server it spawned together,
where the default ClaudeWrapper.Runner.Port would leave them running
(see #185).
This module compiles only when forcola is a dependency. Select it
with config :claude_wrapper, runner: ClaudeWrapper.Runner.Forcola.
forcola is POSIX-only.