feat: Add OTEL based observability to the Go Feature Server

[shuchu]

What this PR does / why we need it:

Add OTEL based observability to Go Feature Server

Which issue(s) this PR fixes:

Fix #4821

Misc

[Copilot]

Pull Request Overview

This PR adds OpenTelemetry (OTEL) based observability to the Go Feature Server, replacing the previously commented-out DataDog tracing implementation. The changes enable distributed tracing through OTEL exporters with support for Jaeger and Prometheus monitoring.

Key changes:

• Integrated OTEL tracing SDK with HTTP exporter configuration
• Added tracing instrumentation across critical code paths (HTTP/gRPC servers, Redis store, transformations)
• Provided Docker Compose setup with Prometheus, Jaeger, and OTEL collector for local monitoring

Reviewed Changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
go/main.go	Initializes OTEL tracer provider and exporter based on environment variable
go/internal/feast/transformation/transformation.go	Adds span tracing to transformation operations
go/internal/feast/server/server_commons.go	Updates logging to include trace/span context from OTEL spans
go/internal/feast/server/http_server.go	Instruments HTTP endpoint with tracing and restores span-aware logging
go/internal/feast/server/grpc_server.go	Instruments gRPC endpoint with tracing and restores span-aware logging
go/internal/feast/onlinestore/redisonlinestore.go	Adds tracing to Redis online store read operations
go/internal/feast/featurestore.go	Instruments feature store read operations with tracing
go/infra/docker/otel/prometheus.yaml	Prometheus scrape configuration for OTEL collector metrics
go/infra/docker/otel/otel-collector-config.yaml	OTEL collector pipeline configuration for traces and metrics
go/infra/docker/otel/compose.yaml	Docker Compose setup for monitoring infrastructure
go/README.md	Documentation for OTEL observability setup and configuration
go.mod	Updates Go version and adds OTEL dependencies

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[Copilot]

Pull Request Overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated 2 comments.

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[ntkathole]

probably this needs to be execute before server stop ?

[ntkathole]

Looks good