Add optional icons field to RawResourceTemplate (#589)

* feat: add optional icons field to RawResourceTemplate

* chore: update JSON schema for ResourceTemplate icons

crates/rmcp/src/model/resource.rs

@@ -48,6 +48,9 @@ pub struct RawResourceTemplate {
     pub description: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub mime_type: Option<String>,
+    /// Optional list of icons for the resource template
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub icons: Option<Vec<Icon>>,
 }
 
 pub type ResourceTemplate = Annotated<RawResourceTemplate>;
@@ -146,4 +149,40 @@ mod tests {
         assert!(json.contains("mimeType"));
         assert!(!json.contains("mime_type"));
     }
+
+    #[test]
+    fn test_resource_template_with_icons() {
+        let resource_template = RawResourceTemplate {
+            uri_template: "file:///{path}".to_string(),
+            name: "template".to_string(),
+            title: Some("Test Template".to_string()),
+            description: Some("A test resource template".to_string()),
+            mime_type: Some("text/plain".to_string()),
+            icons: Some(vec![Icon {
+                src: "https://example.com/icon.png".to_string(),
+                mime_type: Some("image/png".to_string()),
+                sizes: Some(vec!["48x48".to_string()]),
+            }]),
+        };
+
+        let json = serde_json::to_value(&resource_template).unwrap();
+        assert!(json["icons"].is_array());
+        assert_eq!(json["icons"][0]["src"], "https://example.com/icon.png");
+        assert_eq!(json["icons"][0]["sizes"][0], "48x48");
+    }
+
+    #[test]
+    fn test_resource_template_without_icons() {
+        let resource_template = RawResourceTemplate {
+            uri_template: "file:///{path}".to_string(),
+            name: "template".to_string(),
+            title: None,
+            description: None,
+            mime_type: None,
+            icons: None,
+        };
+
+        let json = serde_json::to_value(&resource_template).unwrap();
+        assert!(json.get("icons").is_none());
+    }
 }

crates/rmcp/tests/test_message_schema/server_json_rpc_message_schema.json

@@ -263,6 +263,16 @@
             "null"
           ]
         },
+        "icons": {
+          "description": "Optional list of icons for the resource template",
+          "type": [
+            "array",
+            "null"
+          ],
+          "items": {
+            "$ref": "#/definitions/Icon"
+          }
+        },
         "mimeType": {
           "type": [
             "string",

crates/rmcp/tests/test_message_schema/server_json_rpc_message_schema_current.json

@@ -263,6 +263,16 @@
             "null"
           ]
         },
+        "icons": {
+          "description": "Optional list of icons for the resource template",
+          "type": [
+            "array",
+            "null"
+          ],
+          "items": {
+            "$ref": "#/definitions/Icon"
+          }
+        },
         "mimeType": {
           "type": [
             "string",