feat: Introduce a /reset command to clear the chat session and token tracking, and update documentation.

ChatSession.cs

@@ -11,7 +11,7 @@ internal sealed class ChatSession
     public ChatSession(IChatClient innerClient)
     {
         Compactor = new ContextCompactor(innerClient);
-        
+
         var tools = ToolRegistry.GetTools();
         _agent = new ChatClientBuilder(innerClient)
             .UseFunctionInvocation()
@@ -34,23 +34,36 @@ internal sealed class ChatSession
                 Never include the "lineNumber:hash|" prefix in content you write — it will corrupt the file.
 
                 ## Workflow
-                1. Always read a file before editing it.
-                2. After a mutation, verify the returned fingerprint.
+                1. ALWAYS call GrepFile before ReadFile on any source file.
+                   Use patterns like "public|func|function|class|interface|enum|def|fn " to get a structural
+                   outline of the file and identify the exact line numbers of the section you need.
+                   Only then call ReadFile with a targeted startLine/endLine range.
+                   ❌ WRONG: ReadFile("Foo.cs") — reads blindly without knowing the structure.
+                   ✅ RIGHT: GrepFile("Foo.cs", "public|class|interface") → ReadFile("Foo.cs", 42, 90)
+                2. After reading, edit the file before verifying the returned fingerprint.
                 3. Edit from bottom to top so line numbers don't shift.
-                4. If an anchor fails validation, re-read the file to get fresh anchors.
+                4. If an anchor fails validation, re-read the relevant range to get fresh anchors.
 
                 Keep responses concise. You have access to the current working directory.
                 You are running on: {{System.Runtime.InteropServices.RuntimeInformation.OSDescription}}
             """)
         };
     }
+    public void Reset()
+    {
+        // Keep only the system message
+        var systemMessage = History[0];
+        History.Clear();
+        History.Add(systemMessage);
+    }
+
 
     public async IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(
         [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken = default)
     {
         var options = new ChatOptions { Tools = ToolRegistry.GetTools() };
         var stream = _agent.GetStreamingResponseAsync(History, options, cancellationToken);
-        
+
         await foreach (var update in stream.WithCancellation(cancellationToken))
         {
             yield return update;