Update project files and dependencies to resolve Build issues.

- Removed `ElsaStudioVersion` from `Directory.Build.props`.
- Added `PackageVersions` group in `Directory.Packages.props` with `ElsaStudioVersion` and new `Moq` package version.
- Updated input retrieval method in `ConfigureLiquidEngine.cs` to use `ActivityInput`.
- Clarified import for `InvokingActivityCallback` in `ScheduledChildCallbackBehavior.cs`.
- Changed target framework to `net9.0` in `Elsa.Http.UnitTests.csproj` and updated package references for flexibility.

Author: KnibbsyMan

Directory.Build.props

@@ -36,7 +36,4 @@
         <!-- IL trimming warnings -->
         <NoWarn>$(NoWarn);IL2026;IL2046;IL2057;IL2067;IL2070;IL2072;IL2075;IL2087;IL2091</NoWarn>
     </PropertyGroup>
-    <PropertyGroup>
-        <ElsaStudioVersion>3.6.0-preview.1029</ElsaStudioVersion>
-    </PropertyGroup>
 </Project>

Directory.Packages.props

@@ -4,6 +4,10 @@
 		<CentralPackageTransitivePinningEnabled>false</CentralPackageTransitivePinningEnabled>
 	</PropertyGroup>
 
+	<PropertyGroup Label="PackageVersions">
+		<ElsaStudioVersion>3.6.0-preview.1029</ElsaStudioVersion>
+	</PropertyGroup>
+	
   <ItemGroup Label="Elsa">
     <PackageVersion Include="Elsa.Actors.ProtoActor" Version="3.6.0-preview.29" />
     <PackageVersion Include="Elsa.Alterations" Version="3.6.0-preview.29" />
@@ -156,6 +160,7 @@
     <PackageVersion Include="Microsoft.Identity.Client" Version="4.71.1" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.14.0" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
+	<PackageVersion Include="Moq" Version="4.20.72" />
     <PackageVersion Include="MySql.Data" Version="9.3.0" />
     <PackageVersion Include="MongoDB.Driver" Version="3.4.0" />
     <PackageVersion Include="MongoDB.Driver.Core.Extensions.DiagnosticSources" Version="2.0.0" />

src/modules/Elsa.Expressions.Liquid/Handlers/ConfigureLiquidEngine.cs

@@ -77,7 +77,7 @@ private Task<FluidValue> GetInput(ExpressionExecutionContext context, string key
     {
         // First, check if the current activity has inputs
         if (context.TryGetActivityExecutionContext(out var activityExecutionContext) &&
-            activityExecutionContext.Input.TryGetValue(key, out var activityValue))
+            activityExecutionContext.ActivityInput.TryGetValue(key, out var activityValue))
         {
             return Task.FromResult(activityValue == null ? NilValue.Instance : FluidValue.Create(activityValue, options));
         }

src/modules/Elsa.Workflows.Core/Behaviors/ScheduledChildCallbackBehavior.cs

@@ -1,5 +1,4 @@
 using Elsa.Mediator.Contracts;
-using Elsa.Workflows.Notifications;
 using Elsa.Workflows.Signals;
 using JetBrains.Annotations;
 
@@ -31,7 +30,7 @@ private async ValueTask OnActivityCompletedAsync(ActivityCompleted signal, Signa
             completedContext.TargetContext.Tag = tag;
 
             var mediator = activityExecutionContext.GetRequiredService<IMediator>();
-            var invokingActivityCallbackNotification = new InvokingActivityCallback(activityExecutionContext, childActivityExecutionContext);
+            var invokingActivityCallbackNotification = new Notifications.InvokingActivityCallback(activityExecutionContext, childActivityExecutionContext);
             await mediator.SendAsync(invokingActivityCallbackNotification, context.CancellationToken);
 
             await callbackEntry.CompletionCallback(completedContext);

test/unit/Elsa.Http.UnitTests/Elsa.Http.UnitTests.csproj

@@ -1,7 +1,7 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFramework>net8.0</TargetFramework>
+        <TargetFramework>net9.0</TargetFramework>
         <ImplicitUsings>enable</ImplicitUsings>
         <Nullable>enable</Nullable>
         <LangVersion>latest</LangVersion>
@@ -10,14 +10,14 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
-        <PackageReference Include="Moq" Version="4.20.70" />
-        <PackageReference Include="xunit" Version="2.7.0" />
-        <PackageReference Include="xunit.runner.visualstudio" Version="2.5.7">
+        <PackageReference Include="Microsoft.NET.Test.Sdk" />
+        <PackageReference Include="Moq" />
+        <PackageReference Include="xunit" />
+        <PackageReference Include="xunit.runner.visualstudio" >
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
             <PrivateAssets>all</PrivateAssets>
         </PackageReference>
-        <PackageReference Include="coverlet.collector" Version="6.0.0">
+        <PackageReference Include="coverlet.collector" >
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
             <PrivateAssets>all</PrivateAssets>
         </PackageReference>