fn validate_session_id(id: &str) -> Result<()>Expand description
Rejects a session id that would let chisel-<id>.json escape the cache directory when
concatenated into a path (e.g. ../../etc/cron.d/evil, which yields the literal path
component chisel-.., followed by a real .. component once the id itself contains a /).
Also rejects : to prevent targeting Windows Alternate Data Streams (ADS).