ALCD's lower 7 bits are a bitmap of category flags per E5 §10.3 and
E30 §6.13; a single alarm may carry multiple categories at once
(e.g. an irrecoverable equipment-safety fault is 0x10 | 0x02).
Adds:
enum class AlarmSeverity : uint8_t
PersonalSafety EquipmentSafety ParameterError ParameterWarning
Irrecoverable EquipmentStatus Attention
has_severity(alcd, bit), severity_bits(alcd)
Alarm::has(bit), Alarm::is_safety()
constexpr severity_mask = 0x7F
Tests cover single-category alarms, multi-category combos, and that
the bit-7 SET/CLEAR flag is correctly excluded from category bits.
Closes Tranche C (E5 alarm/exception state model).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
raphael
c163d2060f