docs: update roots terminology to match MCP spec clarification

Agent-Logs-Url: https://github.com/modelcontextprotocol/csharp-sdk/sessions/2ab95d23-a5b8-4211-8ea7-a5cdf7a15861

Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>

Author: Copilot

docs/concepts/roots/roots.md

@@ -17,7 +17,7 @@ Roots provide a mechanism for the client to tell the server which directories, p
 
 - Scope file searches to the user's project directories
 - Understand which repositories are being worked on
-- Limit operations to specific filesystem boundaries
+- Focus operations on relevant filesystem locations
 
 Each root is represented by a <xref:ModelContextProtocol.Protocol.Root> with a URI and an optional human-readable name.
 

src/ModelContextProtocol.Core/Protocol/NotificationMethods.cs

@@ -53,9 +53,10 @@ public static class NotificationMethods
     /// <remarks>
     /// <para>
     /// This notification informs the server that the client's "roots" have changed.
-    /// Roots define the boundaries of where servers can operate within the filesystem,
-    /// allowing them to understand which directories and files they have access to. Servers
-    /// can request the list of roots from supporting clients and receive notifications when that list changes.
+    /// Roots inform servers about the directories and files the client considers relevant,
+    /// so that servers can focus their operations accordingly. They are informational guidance
+    /// rather than an access-control mechanism; the protocol does not enforce that servers stay within roots.
+    /// Servers can request the list of roots from supporting clients and receive notifications when that list changes.
     /// </para>
     /// <para>
     /// After receiving this notification, servers can refresh their knowledge of roots by calling the appropriate