refactor: centralize build config and pin the SDK (#156) (#182)

Adds global.json (10.0 SDK, rollForward latestFeature) so local dev
resolves the same SDK line CI pins in five workflows, instead of
floating to whatever is installed.

Adds Directory.Build.props for LangVersion/Nullable, the two
properties identical across all three csproj (TargetFramework stays
per-project since the test project multi-targets net10.0;net48).

Adds Directory.Packages.props with central package management, moving
every PackageReference version out of the three csproj into one file.
Newtonsoft.Json bumped 13.0.3 -> 13.0.4 in the single place instead of
two independent declarations that could drift. xunit.runner.visualstudio
stays at 4.0.0 (it runs xUnit v1/v2/v3 per its own description; nothing
in the issue's stated xunit 2.9.3 pairing required a downgrade).

Removes the self-referential $(NoWarn) from the Core csproj, a no-op.

Adds an explicit System.Memory 4.6.3 PackageReference to the net48
leg of the test project, which resolves the MSB3277 conflict between
System.Memory 4.0.1.2 and 4.0.5.0 (110 warnings -> 0). Scoped to net48
only per the issue, which names only the net48 test target.

Adds PackageVersionCentralizationTests, an xUnit test asserting none
of the three csproj declare a PackageReference Version attribute
outside Directory.Packages.props.

Co-authored-by: goodolclint-claude[bot] <323206664+goodolclint-claude[bot]@users.noreply.github.com>

Directory.Build.props

@@ -0,0 +1,8 @@
+<Project>
+
+  <PropertyGroup>
+    <LangVersion>10.0</LangVersion>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

Directory.Packages.props

@@ -0,0 +1,19 @@
+<Project>
+
+  <PropertyGroup>
+    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageVersion Include="Newtonsoft.Json" Version="13.0.4" />
+    <PackageVersion Include="PowerShellStandard.Library" Version="5.1.1" />
+    <PackageVersion Include="SharpCompress" Version="0.50.4" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
+    <PackageVersion Include="xunit" Version="2.9.3" />
+    <PackageVersion Include="xunit.runner.visualstudio" Version="4.0.0" />
+    <PackageVersion Include="Moq" Version="4.20.72" />
+    <PackageVersion Include="coverlet.collector" Version="10.0.1" />
+    <PackageVersion Include="System.Memory" Version="4.6.3" />
+  </ItemGroup>
+
+</Project>

global.json

@@ -0,0 +1,6 @@
+{
+  "sdk": {
+    "version": "10.0.100",
+    "rollForward": "latestFeature"
+  }
+}

src/PSProxmoxVE.Core/PSProxmoxVE.Core.csproj

@@ -2,12 +2,9 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>10.0</LangVersion>
-    <Nullable>enable</Nullable>
     <RootNamespace>PSProxmoxVE.Core</RootNamespace>
     <AssemblyName>PSProxmoxVE.Core</AssemblyName>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
-    <NoWarn>$(NoWarn)</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>
@@ -17,8 +14,8 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
-    <PackageReference Include="SharpCompress" Version="0.50.4" />
+    <PackageReference Include="Newtonsoft.Json" />
+    <PackageReference Include="SharpCompress" />
   </ItemGroup>
 
 </Project>

src/PSProxmoxVE/PSProxmoxVE.csproj

@@ -2,8 +2,6 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>10.0</LangVersion>
-    <Nullable>enable</Nullable>
     <RootNamespace>PSProxmoxVE</RootNamespace>
     <AssemblyName>PSProxmoxVE</AssemblyName>
     <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
@@ -11,8 +9,8 @@
 
   <ItemGroup>
     <ProjectReference Include="..\PSProxmoxVE.Core\PSProxmoxVE.Core.csproj" />
-    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
-    <PackageReference Include="PowerShellStandard.Library" Version="5.1.1" PrivateAssets="all" />
+    <PackageReference Include="Newtonsoft.Json" />
+    <PackageReference Include="PowerShellStandard.Library" PrivateAssets="all" />
   </ItemGroup>
 
   <ItemGroup>

tests/PSProxmoxVE.Core.Tests/PSProxmoxVE.Core.Tests.csproj

@@ -2,21 +2,19 @@
 
   <PropertyGroup>
     <TargetFrameworks>net10.0;net48</TargetFrameworks>
-    <LangVersion>10.0</LangVersion>
-    <Nullable>enable</Nullable>
     <IsPackable>false</IsPackable>
     <IsTestProject>true</IsTestProject>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
-    <PackageReference Include="xunit" Version="2.9.3" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="4.0.0">
+    <PackageReference Include="Microsoft.NET.Test.Sdk" />
+    <PackageReference Include="xunit" />
+    <PackageReference Include="xunit.runner.visualstudio">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Moq" Version="4.20.72" />
-    <PackageReference Include="coverlet.collector" Version="10.0.1">
+    <PackageReference Include="Moq" />
+    <PackageReference Include="coverlet.collector">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
@@ -28,6 +26,7 @@
 
   <ItemGroup Condition="'$(TargetFramework)' == 'net48'">
     <Reference Include="System.Net.Http" />
+    <PackageReference Include="System.Memory" />
   </ItemGroup>
 
   <ItemGroup>

tests/PSProxmoxVE.Core.Tests/PackageVersionCentralizationTests.cs

@@ -0,0 +1,53 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Xml.Linq;
+using Xunit;
+
+namespace PSProxmoxVE.Core.Tests
+{
+    public class PackageVersionCentralizationTests
+    {
+        private static readonly string[] ProjectPaths =
+        {
+            "src/PSProxmoxVE.Core/PSProxmoxVE.Core.csproj",
+            "src/PSProxmoxVE/PSProxmoxVE.csproj",
+            "tests/PSProxmoxVE.Core.Tests/PSProxmoxVE.Core.Tests.csproj",
+        };
+
+        [Fact]
+        public void PackageReferences_DoNotPinVersionsPerProject()
+        {
+            var repoRoot = FindRepoRoot();
+
+            foreach (var relativePath in ProjectPaths)
+            {
+                var doc = XDocument.Load(Path.Combine(repoRoot, relativePath));
+                var pinned = doc.Descendants("PackageReference")
+                    .Where(e => e.Attribute("Version") != null)
+                    .Select(e => e.Attribute("Include")?.Value)
+                    .ToList();
+
+                Assert.True(pinned.Count == 0,
+                    $"{relativePath} pins a version directly instead of going through Directory.Packages.props: {string.Join(", ", pinned)}");
+            }
+        }
+
+        private static string FindRepoRoot()
+        {
+            var dir = new DirectoryInfo(AppContext.BaseDirectory);
+            while (dir != null && !File.Exists(Path.Combine(dir.FullName, "PSProxmoxVE.sln")))
+            {
+                dir = dir.Parent;
+            }
+
+            if (dir == null)
+            {
+                throw new InvalidOperationException(
+                    "Could not locate repository root (PSProxmoxVE.sln) from " + AppContext.BaseDirectory);
+            }
+
+            return dir.FullName;
+        }
+    }
+}