epic: Shift threads and messages back to Jan

[david-menloai]

Shift Threads and Messages from cortex.cpp to Jan - Application Business Layer

Goal

Move threads and messages handling to Jan’s application/business layer, decoupling them from the cortex.cpp server. This will allow different clients (e.g., desktop app, web app, mobile) to handle presentation and storage of thread/message data according to their own needs.

Description

Currently, threads and messages are managed within the cortex.cpp server. This setup couples core data (threads and messages) too tightly with a specific backend implementation, which limits flexibility and reusability across different client applications.

Tasks

• Define a shared interface/contract for threads and messages in the business layer
• Move thread/message persistence and state management into Jan
• Update integration between Jan and cortex.cpp to route only inference/completion data

Benefits:

• More modular architecture
• Faster to deliver multiple client apps
• Simplifies cortex.cpp server to focus solely on inference logic

Impact:

This is a breaking change for client apps currently relying on thread/message data coming from cortex.cpp.

[louis-menlo]

Updated issue description.