{"agent":"claude","input":"Add OpenTelemetry tracing to this Gin API. Read hello.go, common/database.go, users/middlewares.go, AGENTS.md, go.mod, .env.example and .github/workflows/ci.yml first. Check which Go version the current otel, otelgin and gorm.io/plugin/opentelemetry modules need against the go directive and the CI matrix, and say what you changed about either. Add common/telemetry.go with a tracer provider, a service-name resource and an OTLP HTTP exporter configured by OTEL_SERVICE_NAME and OTEL_EXPORTER_OTLP_ENDPOINT, with shutdown called from main. Add otelgin.Middleware to the router and the GORM tracing plugin to common.Init. Document both variables in .env.example. Add tests with an in-memory span exporter that assert a server span for GET /api/ping and a database child span for user registration. Run the binary with a stdout exporter, make a registration and an article request, and keep the span output. Run scripts/gofmt.sh, scripts/coverage.sh and golangci-lint, and open a pull request with the span output.","resources":[{"url":"https://github.com/your-org/your-app"}]}