Serving metrics: move query and aggregation ownership to Console #19

Disposition

The original proposal to implement per-service serving-metrics queries and aggregation in swissd has been superseded. This work is now tracked end to end in modelsphere/console#55.

Ownership decision

• Swiss remains responsible for model deployment operations, deployment state, and deployment operation records.
• Console is the unified entry point for the whole ModelSphere platform. For this delivery, its backend will query the existing Prometheus directly and aggregate serving metrics for its frontend.
• Console #55 covers metric-source verification, metric definitions, service/resource label mappings, the authenticated read-only backend interface, dashboard integration, and tests.
• The browser will access metrics through Console, not directly through Prometheus.
• Missing sources and failed queries must remain unknown rather than becoming zero-filled curves.

browser -> Console (authentication, authorization, metrics query/aggregation) -> Prometheus
browser -> Console -> Swiss (deployment operations and state)

Removed proposal and dependency

• Do not implement the previously proposed GET /api/metrics/overview?from=&to= endpoint in swissd under this issue.
• A Swiss metrics endpoint, backend release, or unmerged /api/runs/timeline prototype is not a prerequisite for Console #55.
• Earlier comments describing a Swiss metrics implementation/release as a prerequisite are superseded by this decision.

Closure

Close this issue as not planned in Swiss because the work is tracked in Console #55. This closure does not mean that serving metrics have been implemented or released. If implementation identifies a concrete deployment-metadata gap that Swiss must address, track that narrowly scoped requirement separately.