Splits the side-effecting half of Phase7Composer (deferred at Task 47)
into two pieces that mirror DriverHostActor's spawn-plan pattern:
Phase7Plan + Phase7Planner.Compute (pure):
Diff two Phase7CompositionResult snapshots by stable id (EquipmentId,
DriverInstanceId, ScriptedAlarmId). Emits Added/Removed/Changed lists
per entity class. Added/Removed are sorted by id for deterministic
apply order. Changed wraps both Previous and Current projections so
consumers can decide between in-place mutation and tear-down +
rebuild.
Phase7Applier (side-effecting):
Drives an IOpcUaAddressSpaceSink against a plan. Removed equipment/
alarms get an inactive AlarmState write per id; Added/Removed of
Equipment or ScriptedAlarm triggers RebuildAddressSpace. Driver-only
changes correctly skip the rebuild — those flow through DriverHost-
Actor's spawn-plan in Runtime. Sink exceptions are caught + logged so
one bad node doesn't abort the apply.
Tests: OpcUaServer 6 -> 20 (+14):
- Phase7PlannerTests x9 (empty-in/empty-out, add/remove/change per
entity class, mixed changes, deterministic ordering)
- Phase7ApplierTests x5 (empty plan no-op, removal writes inactive
states + rebuild, added equipment triggers rebuild, driver-only
skips rebuild, sink fault is non-fatal)
The remaining piece is the EquipmentNodeWalker integration against a
real SDK NodeManager — split as F14b, gated on F10b's SDK builder.
All 6 v2 test suites green: 146 tests passing.
