DriverArrayWriteSupport (Core.Abstractions, not this lane's) still lists
AbLegacy as scalar-only, so every AbLegacy array node is materialised
read-only and the new array encoder is unreachable from OPC UA. Adds the
Modbus/S7-style parity test, skipped until follow-up F1 adds the AbLegacy row
(Int/AnalogInt/Long/Float with a declared length), plus an active test pinning
exactly which element types the encoder accepts.
Refs #738
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT