Clarify the behavior of FilePatternMatch Path and Stem (dotnet#5348)

Related: dotnet/runtime#36092 (issue) and dotnet/runtime#48093 (PR)

Author: jeffhandley

xml/Microsoft.Extensions.FileSystemGlobbing/FilePatternMatch.xml

@@ -53,8 +53,8 @@
         <Parameter Name="stem" Type="System.String" />
       </Parameters>
       <Docs>
-        <param name="path">The path to the matched file</param>
-        <param name="stem">The stem</param>
+        <param name="path">The path to the file matched, relative to the beginning of the matching search pattern.</param>
+        <param name="stem">The subpath to the file matched, relative to the first wildcard in the matching search pattern.</param>
         <summary>Initializes new instance of <see cref="T:Microsoft.Extensions.FileSystemGlobbing.FilePatternMatch" /></summary>
         <remarks>To be added.</remarks>
       </Docs>
@@ -180,10 +180,10 @@
         <ReturnType>System.String</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>The path to the file matched.</summary>
+        <summary>The path to the file matched, relative to the beginning of the matching search pattern.</summary>
         <value>To be added.</value>
-        <remarks>If the matcher searched for "**/*.cs" using "src/Project" as the directory base and the pattern matcher found
-            "src/Project/Interfaces/IFile.cs", then Stem = "Interfaces/IFile.cs" and Path = "src/Project/Interfaces/IFile.cs".</remarks>
+        <remarks>If the matcher searched for "src/Project/**/*.cs" and the pattern matcher found "src/Project/Interfaces/IFile.cs",
+          then <see cref="Stem" /> = "Interfaces/IFile.cs" and <see cref="Path" /> = "src/Project/Interfaces/IFile.cs".</remarks>
       </Docs>
     </Member>
     <Member MemberName="Stem">
@@ -209,11 +209,10 @@
         <ReturnType>System.String</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>The subpath to the matched file under the base directory searched.</summary>
+        <summary>The subpath to the file matched, relative to the first wildcard in the matching search pattern.</summary>
         <value>To be added.</value>
-        <remarks>If the matcher searched for "**/*.cs" using "src/Project" as the directory base and the pattern matcher found
-            "src/Project/Interfaces/IFile.cs",
-            then Stem = "Interfaces/IFile.cs" and Path = "src/Project/Interfaces/IFile.cs".</remarks>
+        <remarks>If the matcher searched for "src/Project/**/*.cs" and the pattern matcher found "src/Project/Interfaces/IFile.cs",
+          then <see cref="Stem" /> = "Interfaces/IFile.cs" and <see cref="Path" /> = "src/Project/Interfaces/IFile.cs".</remarks>
       </Docs>
     </Member>
   </Members>