/// Pin buffer memory to RAM using mlock
///
/// Attempts to lock the buffer in physical RAM to prevent swapping.
/// This is useful for security-sensitive data or latency-critical operations.
///
/// # Best-effort
///
/// Pinning may fail due to:
/// - Insufficient permissions (needs CAP_IPC_LOCK on Linux)
/// - Resource limits (RLIMIT_MEMLOCK)
/// - Platform limitations
///
/// Failures are silently ignored as this is an optimization, not a requirement.
pub