Port SetForegroundSessionRequest from reference implementation (c63feb2)

Agent-Logs-Url: https://github.com/github/copilot-sdk-java/sessions/4b8200da-787f-4f51-ab9d-c196711007de

Co-authored-by: edburns <75821+edburns@users.noreply.github.com>

src/main/java/com/github/copilot/sdk/CopilotClient.java

@@ -744,18 +744,15 @@ public CompletableFuture<String> getForegroundSessionId() {
      *             if the operation fails
      */
     public CompletableFuture<Void> setForegroundSessionId(String sessionId) {
-        return ensureConnected()
-                .thenCompose(
-                        connection -> connection.rpc
-                                .invoke("session.setForeground", Map.of("sessionId", sessionId),
-                                        com.github.copilot.sdk.json.SetForegroundSessionResponse.class)
-                                .thenAccept(response -> {
-                                    if (!response.success()) {
-                                        throw new RuntimeException(response.error() != null
-                                                ? response.error()
-                                                : "Failed to set foreground session");
-                                    }
-                                }));
+        return ensureConnected().thenCompose(connection -> connection.rpc
+                .invoke("session.setForeground", new com.github.copilot.sdk.json.SetForegroundSessionRequest(sessionId),
+                        com.github.copilot.sdk.json.SetForegroundSessionResponse.class)
+                .thenAccept(response -> {
+                    if (!response.success()) {
+                        throw new RuntimeException(
+                                response.error() != null ? response.error() : "Failed to set foreground session");
+                    }
+                }));
     }
 
     /**

src/main/java/com/github/copilot/sdk/json/SetForegroundSessionRequest.java

@@ -0,0 +1,18 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+package com.github.copilot.sdk.json;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Internal request object for setting the foreground session.
+ *
+ * @param sessionId
+ *            the ID of the session to set as the foreground session
+ * @see com.github.copilot.sdk.CopilotClient#setForegroundSessionId(String)
+ * @since 1.0.0
+ */
+public record SetForegroundSessionRequest(@JsonProperty("sessionId") String sessionId) {
+}