feat: Implement conversation history

[changxubo]

Changes:

1. Conversation history and langgraph event will be automatically when the checkpointing be configured
2. Add Conversation History dialog in frontend
3. Support Postgres and MongoDB as storage
4. Auto create the following tables if you select Postgres as checkpointing db:

• chat-streams: Store all messages-chunks of the conversation
• checkpoint_blobs: Default table of langgraph checkpoint
• checkpoint_migrations: Default table of langgraph checkpoint
• checkpoint_writes: Default table of langgraph checkpoint
• checkpoints: Default table of langgraph checkpoint
• langgraph_events: Store all events of langgraph node
• research_replays: Store all research replays

5. Auto create the following collections if you select MongoDB as checkpointing db:

• chat-streams: Store all messages-chunks of the conversation
• checkpoint_writes_aio: Default table of langgraph checkpoint
• checkpoint_aio: Default table of langgraph checkpoint
• langgraph_events: Store all events of langgraph node
• research_replays: Store all research replays

6. UI features as following:

[jiaoqiyuan]

Need it, please review. @WillemJiang

[WillemJiang]

@changxubo, could you take a look at the lint error of the web front-end?

[changxubo]

@WillemJiang Fixed ,please review!

[jiaoqiyuan]

@WillemJiang Is this PR ready to be merged?

[Jessewu79]

@WillemJiang @changxubo 你好，请问这个历史回放的代码什么时候可以合并到主分支，谢谢

[jiaoqiyuan]

或许这个功能在添加用户管理之后再合并到项目中会比较好，否则多用户情况下大家的历史记录不好管理，每个人都能看到别人的历史记录也不太好。

[WillemJiang]

或许这个功能在添加用户管理之后再合并到项目中会比较好，否则多用户情况下大家的历史记录不好管理，每个人都能看到别人的历史记录也不太好。

的确，我们需要先实现用户管理功能之后才能合并这样的功能。