[Feature]: Implement ACP-based AI handler

[Nabil-Salah]

Requirement

• Enable AI-powered trace analysis in Jaeger by adding a backend integration point that can communicate with an ACP-capable sidecar agent.
• This should allow Jaeger Query to accept chat-style analysis requests, forward them to the sidecar, and stream responses back to users in real time.
• As part of the AG-UI to ACP PoC in [Feature]: Implement AG-UI to ACP Jaeger AI (PoC) #8252, Jaeger Query should implement the backend ACP communication slice so it can act as a stateless translator between frontend AI chat requests and an external BYOA sidecar.
• The backend must expose the AI chat route, connect to an ACP-capable sidecar over WebSocket, and stream responses back to the client reliably.

Problem

Jaeger currently does not provide a native ACP communication path from Jaeger Query to an AI sidecar, which blocks delivery of AI-assisted trace analysis workflows.

Without this feature:

1. Users cannot send AI analysis prompts through Jaeger Query.
2. There is no built-in endpoint to proxy prompts/responses to an ACP sidecar.

Proposal

No response

Open questions

No response

[yurishkuro]

please book issues as child issues of the main GenAI ticket (done for this one)