Fix resource subscription handling (#89)

* Fix resource subscription handling
Add resource subscription tests

* Fix typo

* Typo

* small fixes

* Fix concurrency issue with test

* Align with specification schemas

src/mcpdotnet/Protocol/Types/Capabilities.cs

@@ -126,13 +126,13 @@ public record ResourcesCapability
     /// Gets or sets the handler for subscribe to resources messages.
     /// </summary>
     [JsonIgnore]
-    public Func<RequestContext<string>, CancellationToken, Task>? SubscribeToResourcesHandler { get; init; }
+    public Func<RequestContext<SubscribeRequestParams>, CancellationToken, Task<EmptyResult>>? SubscribeToResourcesHandler { get; init; }
 
     /// <summary>
     /// Gets or sets the handler for unsubscribe from resources messages.
     /// </summary>
     [JsonIgnore]
-    public Func<RequestContext<string>, CancellationToken, Task>? UnsubscribeFromResourcesHandler { get; init; }
+    public Func<RequestContext<UnsubscribeRequestParams>, CancellationToken, Task<EmptyResult>>? UnsubscribeFromResourcesHandler { get; init; }
 }
 
 /// <summary>

src/mcpdotnet/Protocol/Types/CompleteResult.cs

@@ -0,0 +1,16 @@
+using System.Text.Json.Serialization;
+
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// The server's response to a completion/complete request
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/2024-11-05/schema.json">See the schema for details</see>
+/// </summary>
+public class CompleteResult
+{
+    /// <summary>
+    /// The completion object containing the completion values.
+    /// </summary>
+    [JsonPropertyName("completion")]
+    public Completion Completion { get; set; } = new Completion();
+}

src/mcpdotnet/Protocol/Types/EmptyResult.cs

@@ -0,0 +1,10 @@
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// An empty result object.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/2024-11-05/schema.json">See the schema for details</see>
+/// </summary>
+public class EmptyResult
+{
+
+}

src/mcpdotnet/Protocol/Types/Reference.cs

@@ -66,15 +66,3 @@ public class Reference
         return true;
     }
 }
-
-/// <summary>
-/// The server's response to a completion/complete request
-/// </summary>
-public class CompleteResult
-{
-    /// <summary>
-    /// The completion object containing the completion values.
-    /// </summary>
-    [JsonPropertyName("completion")]
-    public Completion Completion { get; set; } = new Completion();
-}

src/mcpdotnet/Protocol/Types/ResourceUpdatedNotificationParams.cs

@@ -0,0 +1,14 @@
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// Sent from the server as the payload of "notifications/resources/updated" notifications whenever a subscribed resource changes.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/2024-11-05/schema.json">See the schema for details</see>
+/// </summary>
+public class ResourceUpdatedNotificationParams
+{
+    /// <summary>
+    /// The URI of the resource to subscribe to. The URI can use any protocol; it is up to the server how to interpret it.
+    /// </summary>
+    [System.Text.Json.Serialization.JsonPropertyName("uri")]
+    public string? Uri { get; init; }
+}

src/mcpdotnet/Protocol/Types/SubscribeRequestParams.cs

@@ -0,0 +1,14 @@
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// Sent from the client to request updated notifications from the server whenever a particular primitive changes.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/2024-11-05/schema.json">See the schema for details</see>
+/// </summary>
+public class SubscribeRequestParams
+{
+    /// <summary>
+    /// The URI of the resource to subscribe to. The URI can use any protocol; it is up to the server how to interpret it.
+    /// </summary>
+    [System.Text.Json.Serialization.JsonPropertyName("uri")]
+    public string? Uri { get; init; }
+}

src/mcpdotnet/Protocol/Types/UnsubscribeRequestParams.cs

@@ -0,0 +1,14 @@
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// Sent from the client to request not receiving updated notifications from the server whenever a primitive resource changes.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/2024-11-05/schema.json">See the schema for details</see>
+/// </summary>
+public class UnsubscribeRequestParams
+{
+    /// <summary>
+    /// The URI of the resource to unsubscribe fro. The URI can use any protocol; it is up to the server how to interpret it.
+    /// </summary>
+    [System.Text.Json.Serialization.JsonPropertyName("uri")]
+    public string? Uri { get; init; }
+}