feat(scripts): add typed Parameters.Get<T>() helpers for script API

Replace raw dictionary casting with ScriptParameters wrapper that provides
Get<T>, Get<T?>, Get<T[]>, and Get<List<T>> with clear error messages,
numeric conversion, and JsonElement support for Inbound API parameters.

src/ScadaLink.SiteRuntime/Actors/AlarmExecutionActor.cs

@@ -1,6 +1,7 @@
 using Akka.Actor;
 using Microsoft.CodeAnalysis.Scripting;
 using Microsoft.Extensions.Logging;
+using ScadaLink.Commons.Types;
 using ScadaLink.SiteRuntime.Scripts;
 
 namespace ScadaLink.SiteRuntime.Actors;
@@ -64,7 +65,7 @@ public class AlarmExecutionActor : ReceiveActor
                 var globals = new ScriptGlobals
                 {
                     Instance = context,
-                    Parameters = new Dictionary<string, object?>(),
+                    Parameters = new ScriptParameters(),
                     CancellationToken = cts.Token
                 };
 

src/ScadaLink.SiteRuntime/Actors/ScriptExecutionActor.cs

@@ -4,6 +4,7 @@ using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using ScadaLink.Commons.Interfaces.Services;
 using ScadaLink.Commons.Messages.ScriptExecution;
+using ScadaLink.Commons.Types;
 using ScadaLink.HealthMonitoring;
 using ScadaLink.SiteRuntime.Scripts;
 
@@ -100,7 +101,7 @@ public class ScriptExecutionActor : ReceiveActor
                 var globals = new ScriptGlobals
                 {
                     Instance = context,
-                    Parameters = parameters ?? new Dictionary<string, object?>(),
+                    Parameters = new ScriptParameters(parameters ?? new Dictionary<string, object?>()),
                     CancellationToken = cts.Token
                 };
 

src/ScadaLink.SiteRuntime/Scripts/ScriptCompilationService.cs

@@ -3,6 +3,7 @@ using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Scripting;
 using Microsoft.CodeAnalysis.Scripting;
 using Microsoft.Extensions.Logging;
+using ScadaLink.Commons.Types;
 
 namespace ScadaLink.SiteRuntime.Scripts;
 
@@ -177,8 +178,7 @@ public class ScriptCompilationResult
 public class ScriptGlobals
 {
     public ScriptRuntimeContext Instance { get; set; } = null!;
-    public IReadOnlyDictionary<string, object?> Parameters { get; set; } =
-        new Dictionary<string, object?>();
+    public ScriptParameters Parameters { get; set; } = new ScriptParameters();
     public CancellationToken CancellationToken { get; set; }
 
     /// <summary>

src/ScadaLink.SiteRuntime/Scripts/SharedScriptLibrary.cs

@@ -1,5 +1,6 @@
 using Microsoft.CodeAnalysis.Scripting;
 using Microsoft.Extensions.Logging;
+using ScadaLink.Commons.Types;
 
 namespace ScadaLink.SiteRuntime.Scripts;
 
@@ -82,7 +83,7 @@ public class SharedScriptLibrary
         var globals = new ScriptGlobals
         {
             Instance = context,
-            Parameters = parameters ?? new Dictionary<string, object?>(),
+            Parameters = new ScriptParameters(parameters ?? new Dictionary<string, object?>()),
             CancellationToken = cancellationToken
         };