Fix C# "out of sync" notice with external editors

Change what triggers our re-evaluation of the last valid build datetime stored internally.
Move that datetime in `BuildManager`.

modules/mono/editor/GodotTools/GodotTools/Build/BuildManager.cs

@@ -24,6 +24,20 @@ namespace GodotTools.Build
         public static event Action<string> StdOutputReceived;
         public static event Action<string> StdErrorReceived;
 
+        public static DateTime LastValidBuildDateTime { get; private set; }
+
+        static BuildManager()
+        {
+            UpdateLastValidBuildDateTime();
+        }
+
+        public static void UpdateLastValidBuildDateTime()
+        {
+            var dllName = $"{GodotSharpDirs.ProjectAssemblyName}.dll";
+            var path = Path.Combine(GodotSharpDirs.ProjectBaseOutputPath, "Debug", dllName);
+            LastValidBuildDateTime = File.GetLastWriteTime(path);
+        }
+
         private static void RemoveOldIssuesFile(BuildInfo buildInfo)
         {
             string issuesFile = GetIssuesFilePath(buildInfo);

modules/mono/editor/GodotTools/GodotTools/Build/MSBuildPanel.cs

@@ -89,8 +89,11 @@ namespace GodotTools.Build
             GodotSharpEditor.Instance.GetNode<HotReloadAssemblyWatcher>("HotReloadAssemblyWatcher").RestartTimer();
 
             if (Internal.IsAssembliesReloadingNeeded())
+            {
+                BuildManager.UpdateLastValidBuildDateTime();
                 Internal.ReloadAssemblies(softReload: false);
             }
+        }
 
         private void RebuildProject()
         {
@@ -107,8 +110,11 @@ namespace GodotTools.Build
             GodotSharpEditor.Instance.GetNode<HotReloadAssemblyWatcher>("HotReloadAssemblyWatcher").RestartTimer();
 
             if (Internal.IsAssembliesReloadingNeeded())
+            {
+                BuildManager.UpdateLastValidBuildDateTime();
                 Internal.ReloadAssemblies(softReload: false);
             }
+        }
 
         private void CleanProject()
         {

modules/mono/editor/GodotTools/GodotTools/GodotSharpEditor.cs

@@ -54,8 +54,6 @@ namespace GodotTools
 
         public bool SkipBuildBeforePlaying { get; set; } = false;
 
-        public DateTime LastValidBuildDateTime { get; private set; }
-
         [UsedImplicitly]
         private bool CreateProjectSolutionIfNeeded()
         {
@@ -441,21 +439,6 @@ namespace GodotTools
             }
         }
 
-        private void UpdateLastValidBuildDateTime()
-        {
-            var dllName = $"{GodotSharpDirs.ProjectAssemblyName}.dll";
-            var path = Path.Combine(GodotSharpDirs.ProjectBaseOutputPath, "Debug", dllName);
-            LastValidBuildDateTime = File.GetLastWriteTime(path);
-        }
-
-        private void BuildFinished(BuildResult buildResult)
-        {
-            if (buildResult == BuildResult.Success)
-            {
-                UpdateLastValidBuildDateTime();
-            }
-        }
-
         private void BuildStateChanged()
         {
             if (_bottomPanelBtn != null)
@@ -466,8 +449,6 @@ namespace GodotTools
         {
             base._EnablePlugin();
 
-            UpdateLastValidBuildDateTime();
-
             ProjectSettings.SettingsChanged += GodotSharpDirs.DetermineProjectLocation;
 
             if (Instance != null)
@@ -640,7 +621,6 @@ namespace GodotTools
             var inspectorPlugin = new InspectorPlugin();
             AddInspectorPlugin(inspectorPlugin);
             _inspectorPluginWeak = WeakRef(inspectorPlugin);
-            BuildManager.BuildFinished += BuildFinished;
 
             BuildManager.Initialize();
             RiderPathManager.Initialize();
@@ -657,7 +637,6 @@ namespace GodotTools
 
             // Custom signals aren't automatically disconnected currently.
             MSBuildPanel.BuildStateChanged -= BuildStateChanged;
-            BuildManager.BuildFinished -= BuildFinished;
         }
 
         public override void _ExitTree()

modules/mono/editor/GodotTools/GodotTools/HotReloadAssemblyWatcher.cs

@@ -1,7 +1,7 @@
 using Godot;
+using GodotTools.Build;
 using GodotTools.Internals;
 using JetBrains.Annotations;
-using static GodotTools.Internals.Globals;
 
 namespace GodotTools
 {
@@ -16,15 +16,21 @@ namespace GodotTools
                 RestartTimer();
 
                 if (Internal.IsAssembliesReloadingNeeded())
+                {
+                    BuildManager.UpdateLastValidBuildDateTime();
                     Internal.ReloadAssemblies(softReload: false);
                 }
             }
+        }
 
         private void TimerTimeout()
         {
             if (Internal.IsAssembliesReloadingNeeded())
+            {
+                BuildManager.UpdateLastValidBuildDateTime();
                 Internal.ReloadAssemblies(softReload: false);
             }
+        }
 
         [UsedImplicitly]
         public void RestartTimer()

modules/mono/editor/GodotTools/GodotTools/Inspector/InspectorPlugin.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using Godot;
+using GodotTools.Build;
 using GodotTools.Utils;
 
 namespace GodotTools.Inspector
@@ -24,7 +25,7 @@ namespace GodotTools.Inspector
             {
                 if (script is not CSharpScript) continue;
 
-                if (File.GetLastWriteTime(script.ResourcePath) > GodotSharpEditor.Instance.LastValidBuildDateTime)
+                if (File.GetLastWriteTime(script.ResourcePath) > BuildManager.LastValidBuildDateTime)
                 {
                     AddCustomControl(new InspectorOutOfSyncWarning());
                     break;