feat(runtime): per-script execution timeout overriding the global default (#9)

Spec promised a per-script timeout but only the global ScriptExecutionTimeoutSeconds
existed. Add nullable TemplateScript.ExecutionTimeoutSeconds threaded through EF +
flattening (ResolvedScript) to ScriptExecutionActor/AlarmExecutionActor, which use
perScript ?? global for the execution CTS. Includes the EF migration for the new column.

src/ZB.MOM.WW.ScadaBridge.TemplateEngine/Flattening/RevisionHashService.cs

@@ -83,7 +83,10 @@ public class RevisionHashService
                     TriggerConfiguration = s.TriggerConfiguration,
                     ParameterDefinitions = s.ParameterDefinitions,
                     ReturnDefinition = s.ReturnDefinition,
-                    MinTimeBetweenRunsTicks = s.MinTimeBetweenRuns?.Ticks
+                    MinTimeBetweenRunsTicks = s.MinTimeBetweenRuns?.Ticks,
+                    // M2.5 (#9): include the per-script timeout so a change to it
+                    // is detected as a configuration change (staleness/redeploy).
+                    ExecutionTimeoutSeconds = s.ExecutionTimeoutSeconds
                 })
                 .ToList(),
             Connections = configuration.Connections is { Count: > 0 }
@@ -244,6 +247,10 @@ public class RevisionHashService
         /// </summary>
         public string Code { get; init; } = string.Empty;
         /// <summary>
+        /// M2.5 (#9): the per-script execution timeout in seconds (null = global).
+        /// </summary>
+        public int? ExecutionTimeoutSeconds { get; init; }
+        /// <summary>
         /// Whether the script is locked.
         /// </summary>
         public bool IsLocked { get; init; }