When SIMULATE_PLC=true, a background task randomly disrupts rem or flt
signals on equipment (rem=false for 5-15s, flt=true for 3-10s) to
exercise fault detection, comm lock, and recovery logic in the engine.
Uses XorShift64 PRNG with no extra dependencies.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- engine.rs: replace HashSet<Uuid> with HashMap<Uuid, JoinHandle> in
supervise(); use is_finished() to detect exited tasks so units that
are disabled then re-enabled get a new task on next 10s scan
- control/mod.rs: extract shared monitor_value_as_bool (using the more
complete validator version that includes "yes"); remove duplicate
copies from engine.rs and validator.rs
- runtime.rs: fix get_or_create_notify TOCTOU by using entry API
instead of read-drop-write pattern
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
caoqianming