Metrics endpoint 500 fix
GET /api/v1/metrics without Accept header no longer returns 500.
Status: shipped | Area: policy | Published: 2026-03-20
Control impact: Fixes observability endpoint regression.
GET /api/v1/metricswithoutAccept: application/jsonreturned 500 because the route was wrapped in schema validation middleware- Middleware removed from that route; handler already negotiates content type internally