Function record_try_lock_failure 

pub fn record_try_lock_failure(site: &str)

Record one try_lock() failure.

Increments TRY_LOCK_FAILURE_COUNT and emits a CONCURRENCY debug-log entry (visible at DEBUG_LEVEL >= 3).

Arguments

• site - A short, human-readable label identifying the call site (e.g., "resize", "theme_change", "focus_event").