refactor(sdk): introduce session-based architecture (#19180)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/core/src/utils/session.ts

@@ -7,3 +7,7 @@
 import { randomUUID } from 'node:crypto';
 
 export const sessionId = randomUUID();
+
+export function createSessionId(): string {
+  return randomUUID();
+}