Activates the Phase 7 engines in production. Loads Script + VirtualTag +
ScriptedAlarm rows from the bootstrapped generation, wires the engines through
the Phase7EngineComposer kernel (#243), starts the DriverSubscriptionBridge feed
(#244), and late-binds the resulting IReadable sources to OpcUaApplicationHost
before OPC UA server start.
## Phase7Composer (Server.Phase7)
Singleton orchestrator. PrepareAsync loads the three Phase 7 row sets in one
DB scope, builds CachedTagUpstreamSource, calls Phase7EngineComposer.Compose,
constructs DriverSubscriptionBridge with one DriverFeed per registered
ISubscribable driver (path-to-fullRef map built from EquipmentNamespaceContent
via MapPathsToFullRefs), starts the bridge.
DisposeAsync tears down in the right order: bridge first (no more events fired
into the cache), then engines (cascades + timers stop), then any disposable sink.
MapPathsToFullRefs: deterministic path convention is
/{areaName}/{lineName}/{equipmentName}/{tagName}
matching exactly what EquipmentNodeWalker emits into the OPC UA browse tree, so
script literals against the operator-visible UNS tree work without translation.
Tags missing EquipmentId or pointing at unknown Equipment are skipped silently
(Galaxy SystemPlatform-style tags + dangling references handled).
## OpcUaApplicationHost.SetPhase7Sources
New late-bind setter. Throws InvalidOperationException if called after
StartAsync because OtOpcUaServer + DriverNodeManagers capture the field values
at construction; mutation post-start would silently fail.
## OpcUaServerService
After bootstrap loads the current generation, calls phase7Composer.PrepareAsync
+ applicationHost.SetPhase7Sources before applicationHost.StartAsync. StopAsync
disposes Phase7Composer first so the bridge stops feeding the cache before the
OPC UA server tears down its node managers (avoids in-flight cascades surfacing
as noisy shutdown warnings).
## Program.cs
Registers IAlarmHistorianSink as NullAlarmHistorianSink.Instance (task #247
swaps in the real Galaxy.Host-writer-backed SqliteStoreAndForwardSink), Serilog
root logger, and Phase7Composer singleton.
## Tests — 5 new Phase7ComposerMappingTests = 34 Phase 7 tests total
Maps tag → walker UNS path, skips null EquipmentId, skips unknown Equipment
reference, multiple tags under same equipment map distinctly, empty content
yields empty map. Pure functions; no DI/DB needed.
The real PrepareAsync DB query path can't be exercised without SQL Server in
the test environment — it's exercised by the live E2E smoke (task #240) which
unblocks once #247 lands.
## Phase 7 production wiring chain status
- ✅#243 composition kernel
- ✅#245 scripted-alarm IReadable adapter
- ✅#244 driver bridge
- ✅#246 this — Program.cs wire-in
- 🟡#247 — Galaxy.Host SqliteStoreAndForwardSink writer adapter (replaces NullSink)
- 🟡#240 — live E2E smoke (unblocks once #247 lands)
