Clean up namespaces (#410)

No meaningful code changes, just lots of namespace shuffling to have fewer namespaces and to put things in better namespaces.

src/ModelContextProtocol/Protocol/InitializeResult.cs

@@ -0,0 +1,79 @@
+using System.Text.Json.Serialization;
+
+namespace ModelContextProtocol.Protocol;
+
+/// <summary>
+/// Represents the result of a <see cref="RequestMethods.Initialize"/> request sent to the server during connection establishment.
+/// </summary>
+/// <remarks>
+/// <para>
+/// The <see cref="InitializeResult"/> is sent by the server in response to an <see cref="InitializeRequestParams"/> 
+/// message from the client. It contains information about the server, its capabilities, and the protocol version
+/// that will be used for the session.
+/// </para>
+/// <para>
+/// After receiving this response, the client should send an <see cref="NotificationMethods.InitializedNotification"/>
+/// notification to complete the handshake.
+/// </para>
+/// <para>
+/// See the <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/">schema</see> for details.
+/// </para>
+/// </remarks>
+public record InitializeResult
+{
+    /// <summary>
+    /// Gets or sets the version of the Model Context Protocol that the server will use for this session.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// This is the protocol version the server has agreed to use, which should match the client's 
+    /// requested version. If there's a mismatch, the client should throw an exception to prevent 
+    /// communication issues due to incompatible protocol versions.
+    /// </para>
+    /// <para>
+    /// The protocol uses a date-based versioning scheme in the format "YYYY-MM-DD".
+    /// </para>
+    /// <para>
+    /// See the <see href="https://spec.modelcontextprotocol.io/specification/">protocol specification</see> for version details.
+    /// </para>
+    /// </remarks>
+    [JsonPropertyName("protocolVersion")]
+    public required string ProtocolVersion { get; init; }
+
+    /// <summary>
+    /// Gets or sets the server's capabilities.
+    /// </summary>
+    /// <remarks>
+    /// This defines the features the server supports, such as "tools", "prompts", "resources", or "logging", 
+    /// and other protocol-specific functionality.
+    /// </remarks>
+    [JsonPropertyName("capabilities")]
+    public required ServerCapabilities Capabilities { get; init; }
+
+    /// <summary>
+    /// Gets or sets information about the server implementation, including its name and version.
+    /// </summary>
+    /// <remarks>
+    /// This information identifies the server during the initialization handshake.
+    /// Clients may use this information for logging, debugging, or compatibility checks.
+    /// </remarks>
+    [JsonPropertyName("serverInfo")]
+    public required Implementation ServerInfo { get; init; }
+
+    /// <summary>
+    /// Gets or sets optional instructions for using the server and its features.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// These instructions provide guidance to clients on how to effectively use the server's capabilities.
+    /// They can include details about available tools, expected input formats, limitations,
+    /// or any other information that helps clients interact with the server properly.
+    /// </para>
+    /// <para>
+    /// Client applications often use these instructions as system messages for LLM interactions
+    /// to provide context about available functionality.
+    /// </para>
+    /// </remarks>
+    [JsonPropertyName("instructions")]
+    public string? Instructions { get; init; }
+}