Add New PUT Endpoint /conversation_history/

[dave90]

Description

This PR create a new PUT endpoint  /conversation_history/{index} that accept a ConversationMessage  to impose a conversation history (GET and DELETE already exists).

Usage example:

req_json = requests.get("http://localhost:1865/memory/conversation_history")
 req_json = req_json.json()["history"][0]

 req_json["text"] = "MIAO!"
 res = requests.put(
 "http://localhost:1865/memory/conversation_history/0", json=req_json
 )

Related to issue #896

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas

[pieroit]

Thanks @dave90 I'll review asap

[pieroit]

I'm working on v2 and convo history will noty be stored in memory, it will be passed from the client as most app do nowadays. Optionally plugins can retrieve convos in any way and put the history in working memory as they see fit, but I'm moving this feat out of core

PR appreciated but cannot accept it,. sorry. Thanks anyway