Adds agentVersionId to aiCompletionResponse query

What does this MR do and why?

From Adds agentVersionId to aiCompletionResponse sub... (!145945 - merged)

Solves Add agentVersionId to aiCompletionResponse trig... (#441658 - closed)

Adds Ai agents debug chat interface (!141698 - merged) introduced the debug chat for an AI agent. The idea is that you can create an agent with a system prompt and then use a chat interface to debug it (referred to as "debug chat"). We use the same architecture as Duo chat to reuse most parts of the stack.

Because we use the same GraphQl subscription that pushes new messages for both chat interfaces, you'd see all messages on both chat interfaces. So to distinguish between messages for Duo chat and the AI agents debug chat, we need to add the agentVersionId to the subscription. We already use this argument in the mutation. Duo chat will use nil|null and the debug chat will use the agent version global ID, so each chat will only receive messages that are meant for it.

This MR adds the agentVersionId argument to the aiCompletionResponse subscription.

The original MR Adds agentVersionId to aiCompletionResponse sub... (!145945 - merged) has been reverted Revert "Adds agentVersionId to aiCompletionResp... (!146400 - merged) because of a rollout issue on canary (see revert and original MR for details). This is the frontend part of the original MR that we'd like to merge after adding the argument to the GraphQl query via Adds agentVersionId to aiCompletionResponse (!146464 - merged).

❗ !146464 (merged) is a MR dependency

Add agentVersionId to aiCompletionResponse trig... (#441658 - closed)

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See original MR !145945 (merged)

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See original MR !145945 (merged)