Add missing description for prototype decorator.

The prototype label decorator did not provide a description. The
description box in the Label decoration was left empty in the preference
page. This commit adds a description to so that it appears in the
description box like the rest of the entries in the label decorations
preference page.

Author: elsazac

debug/org.eclipse.debug.ui/plugin.properties

@@ -1,5 +1,5 @@
 ###############################################################################
-# Copyright (c) 2000, 2025 IBM Corporation and others.
+# Copyright (c) 2000, 2026 IBM Corporation and others.
 #
 # This program and the accompanying materials
 # are made available under the terms of the Eclipse Public License 2.0
@@ -418,6 +418,7 @@ debug.core.component.label = Platform Debug Core
 GroupLaunch.description=Launch several other configurations sequentially
 
 prototype.decorator.label = Prototype Decorator
+prototype.decorator.description = Decorates launch configurations that are marked as prototypes with an overlay icon.
 breakpointLabel.label= Label
 breakpointLabel.tooltip= Provide a custom label to quickly identify breakpoint
 breakpointLabelCommand = EditBreakpointLabel

debug/org.eclipse.debug.ui/plugin.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <?eclipse version="3.0"?>
 <!--
-     Copyright (c) 2005, 2025 IBM Corporation and others.
+     Copyright (c) 2005, 2026 IBM Corporation and others.
 
      This program and the accompanying materials
      are made available under the terms of the Eclipse Public License 2.0
@@ -3385,6 +3385,9 @@ M4 = Platform-specific fourth key
             lightweight="true"
             location="TOP_RIGHT"
             state="true">
+         <description>
+            %prototype.decorator.description
+         </description>
          <enablement>
             <objectClass
                   name="org.eclipse.debug.internal.core.LaunchConfiguration">