Phase 7 Stream E — Config DB schema for scripts, virtual tags, scripted alarms, and alarm state

Adds the four tables Streams B/C/F consume — Script (generation-scoped source code),
VirtualTag (generation-scoped calculated-tag config), ScriptedAlarm (generation-scoped
alarm config), and ScriptedAlarmState (logical-id-keyed persistent runtime state).

## New entities (net10, EF Core)

- Script — stable logical ScriptId carries across generations; SourceHash is the
  compile-cache key (matches Core.Scripting's CompiledScriptCache).
- VirtualTag — mandatory EquipmentId FK (plan decision #2, unified Equipment tree);
  ChangeTriggered/TimerIntervalMs + Historize flags; check constraints enforce
  "at least one trigger" + "timer >= 50ms".
- ScriptedAlarm — required AlarmType ('AlarmCondition'/'LimitAlarm'/'OffNormalAlarm'/
  'DiscreteAlarm'); Severity 1..1000 range check; HistorizeToAveva default true per
  plan decision #15.
- ScriptedAlarmState — keyed ONLY on ScriptedAlarmId (NOT generation-scoped) per plan
  decision #14 — ack state + audit trail must follow alarm identity across Modified
  generations. CommentsJson has ISJSON check for GxP audit.

## Migration

EF-generated 20260420231641_AddPhase7ScriptingTables covers all 4 tables + indexes +
check constraints + FKs to ConfigGeneration. sp_PublishGeneration required no changes —
it only flips Draft->Published status; the new entities already carry GenerationId so
they publish atomically with the rest of the config.

## Tests — 12/12 (design-time model introspection)

Phase7ScriptingEntitiesTests covers: table registration, column maxlength + column
types, unique indexes (Generation+LogicalId, Generation+EquipmentPath for VirtualTag
and ScriptedAlarm), secondary indexes (SourceHash for cache lookup), check constraints
(trigger-required, timer-min, severity-range, alarm-type-enum, CommentsJson-IsJson),
ScriptedAlarmState PK is alarm-id not generation-scoped, ScriptedAlarm defaults
(HistorizeToAveva=true, Retain=true, Severity=500, Enabled=true), DbSets wired, and
the generated migration type exists for rollforward.

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Script.cs

@@ -0,0 +1,38 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Per Phase 7 plan decision #8 — user-authored C# script source, referenced by
+///     <see cref="VirtualTag"/> and <see cref="ScriptedAlarm"/>. One row per script,
+///     per generation. <c>SourceHash</c> is the compile-cache key.
+/// </summary>
+/// <remarks>
+///     <para>
+///         Scripts are generation-scoped: a draft's edit creates a new row in the draft
+///         generation, the old row stays frozen in the published generation. Shape mirrors
+///         the other generation-scoped entities (Equipment, Tag, etc.) — <c>ScriptId</c> is
+///         the stable logical id that carries across generations; <c>ScriptRowId</c> is the
+///         row identity.
+///     </para>
+/// </remarks>
+public sealed class Script
+{
+    public Guid ScriptRowId { get; set; }
+    public long GenerationId { get; set; }
+
+    /// <summary>Stable logical id. Carries across generations.</summary>
+    public required string ScriptId { get; set; }
+
+    /// <summary>Operator-friendly name for log filtering + Admin UI list view.</summary>
+    public required string Name { get; set; }
+
+    /// <summary>Raw C# source. Size bounded by the DB column (nvarchar(max)).</summary>
+    public required string SourceCode { get; set; }
+
+    /// <summary>SHA-256 of <see cref="SourceCode"/> — compile-cache key for Phase 7 Stream A's <c>CompiledScriptCache</c>.</summary>
+    public required string SourceHash { get; set; }
+
+    /// <summary>Language — always "CSharp" today; placeholder for future engines (Python/Lua).</summary>
+    public string Language { get; set; } = "CSharp";
+
+    public ConfigGeneration? Generation { get; set; }
+}