Memory Provider Interface

interface MemoryProvider {
  get(key: string): Promise<MemoryData>;
  set(key: string, data: MemoryData): Promise<void>;
  append(key: string, message: MemoryMessage): Promise<void>;
  clear(key: string): Promise<void>;
  summarize?(key: string): Promise<string>;
  search?(key: string, query: string): Promise<MemoryMessage[]>;
}