## Why

AIOps payload-targeted diagnosis already scopes the Agent to the supplied alert, but the prompt does not provide a deterministic knowledge-retrieval query. This leaves the Agent to invent lookup terms from the full prompt, which can omit high-value alert fields such as alert name, service, severity, and symptom.

## What Changes

- Build a stable knowledge retrieval query from AIOps payload fields.
- Include the generated retrieval query in payload-targeted prompts as the recommended `lookup_knowledge` query.
- Keep retrieval explicit through the Agent tool; do not automatically call `lookup_knowledge` before the Agent runs.
- Add focused tests for query construction and prompt inclusion.

## Capabilities

### New Capabilities

None.

### Modified Capabilities

- `aiops-traceable-diagnosis-entry`: Payload-targeted AIOps prompts include a deterministic knowledge retrieval query derived from alert payload fields.

## Impact

- Affects `AiOpsService` prompt construction only.
- Does not change the `lookup_knowledge` tool signature, VectorStore retrieval, AIOps API contract, or trace schema.