Enhance TimestampServerManagementForm UI and logic

- Adjusted `progressBar` and `labelInstructions` layout for better alignment.
- Modified button behavior to disable `buttonTest` and `buttonTestAll` in Trusted Signing mode.

Author: michaelmsonne

src/SignToolGUI/Forms/TimestampServerManagementForm.Designer.cs

@@ -78,7 +78,20 @@ private void UpdateButtonStates()
 
             buttonEdit.Enabled = hasSelection;
             buttonRemove.Enabled = hasSelection;
-            buttonTest.Enabled = hasSelection;
+
+            // Disable testing if in Trusted Signing mode
+            if (_isTrustedSigning)
+            {
+                buttonTestAll.Enabled = false;
+                buttonTest.Enabled = false;
+            }
+            else
+            {
+                buttonTestAll.Enabled = hasSelection;
+                buttonTest.Enabled = hasSelection;
+            }
+
+            //buttonTest.Enabled = hasSelection;
             buttonMoveUp.Enabled = hasSelection && selectedIndex > 0;
             buttonMoveDown.Enabled = hasSelection && selectedIndex < listViewServers.Items.Count - 1;
             buttonApply.Enabled = _isModified; // This should enable/disable based on modifications

src/SignToolGUI/Forms/TimestampServerManagementForm.cs

@@ -117,6 +117,10 @@
   <resheader name="writer">
     <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
   </resheader>
+  <data name="labelInstructions.Text" xml:space="preserve">
+    <value>Manage timestamp servers and their priorities. Higher priority servers (lower numbers) are tried first.
+For Trusted Signing - use the Region your Trusted Signing Account is located - else you will get error.</value>
+  </data>
   <assembly alias="System.Drawing" name="System.Drawing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
   <data name="$this.Icon" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
     <value>