Add assembly list to ext. tool Attribute, allows shipping dependencies

DBMan works again

ExternalToolProjects/DBMan/CustomMainForm.cs

@@ -9,7 +9,7 @@ using Community.CsharpSqlite.SQLiteClient;
 
 namespace BizHawk.DBManTool
 {
-	[ExternalTool("DBMan", Description = "DB Manager")]
+	[ExternalTool("DBMan", Description = "DB Manager", LoadAssemblyFiles = new[] { "CSharp-SQLite.dll" })]
 	public class CustomMainForm : Form, IExternalToolForm
 	{
 		public CustomMainForm()

ExternalToolProjects/DBMan/DBMan.csproj

@@ -7,6 +7,7 @@
 		<GenerateResourceUsePreserializedResources>true</GenerateResourceUsePreserializedResources>
 	</PropertyGroup>
 	<ItemGroup>
+		<NET48ExternalToolFormDependency Include="$(ProjectDir)CSharp-SQLite.dll" />
 		<Reference Include="CSharp-SQLite"
 			HintPath="$(ProjectDir)CSharp-SQLite.dll"
 			Private="true" />

ExternalToolProjects/NET48ExternalToolForm.targets

@@ -29,5 +29,6 @@
 	</ItemGroup>
 	<Target Name="PostBuild" AfterTargets="PostBuildEvent">
 		<Copy SourceFiles="$(OutputPath)$(MSBuildProjectName).dll" DestinationFolder="$(ProjectDir)../../output/ExternalTools" />
+		<Copy SourceFiles="@(NET48ExternalToolFormDependency)" DestinationFolder="$(ProjectDir)../../output/ExternalTools" />
 	</Target>
 </Project>

src/BizHawk.Client.Common/Api/ExternalToolAttributes.cs

@@ -98,6 +98,8 @@ namespace BizHawk.Client.Common
 	{
 		public string Description { get; set; }
 
+		public string[] LoadAssemblyFiles { get; set; }
+
 		public readonly string Name;
 
 		public ExternalToolAttribute(string name)

src/BizHawk.Client.EmuHawk/tools/ExternalToolManager.cs

@@ -95,6 +95,10 @@ namespace BizHawk.Client.EmuHawk
 				if (applicabilityAttrs.Count > 1) throw new ExternalToolApplicabilityAttributeBase.DuplicateException();
 
 				var toolAttribute = allAttrs.OfType<ExternalToolAttribute>().First();
+				if (toolAttribute.LoadAssemblyFiles != null)
+				{
+					foreach (var depFilename in toolAttribute.LoadAssemblyFiles) Assembly.LoadFrom($"ExternalTools/{depFilename}");
+				}
 				var embeddedIconAttr = allAttrs.OfType<ExternalToolEmbeddedIconAttribute>().FirstOrDefault();
 				if (embeddedIconAttr != null)
 				{