Better internal logging

[raphael-theriault-swi]

This adds a bunch of internal logging for debugging purposes, using the same environment variable as go otelcol to select the level. I also set the default compression encoding to zstd now that it's been deployed :)

[Copilot]

Pull request overview

This PR migrates internal diagnostic output from eprintln! to tracing, adds request/response tracing middleware, and updates the exporter’s default compression to Zstandard to align with the stated deployment readiness.

Changes:

• Add tracing / tracing-subscriber initialization and instrument key functions for debug-level spans.
• Replace several eprintln! error/warning prints with structured tracing::{warn,error,info}! events.
• Switch default exporter compression from gzip to zstd and add Tower HTTP trace layers.

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
src/util.rs	Logs bound listener addresses via tracing::info!.
src/settings.rs	Instruments settings fetch and replaces eprintln! warnings with tracing::warn!.
src/server/http.rs	Replaces HTTP exporter eprintln! with tracing::warn!.
src/server.rs	Adds TraceLayer for HTTP routes and gRPC routes.
src/requests/telemetry.rs	Instruments telemetry registration for debug tracing.
src/requests/extension.rs	Instruments extension register/next calls for debug tracing.
src/main.rs	Initializes tracing-subscriber with EnvFilter controlled by OPENTELEMETRY_EXTENSION_LOG_LEVEL; replaces lifecycle eprintln! with tracing::error!.
src/exporter.rs	Replaces eprintln! partial-success/error prints with tracing::warn! and instruments export.
src/env.rs	Instruments config parsing and changes default compression to Zstd.
src/detector.rs	Instruments detect for debug tracing.
Cargo.toml	Adds tracing, tracing-subscriber, and enables tower-http trace feature.
Cargo.lock	Updates lockfile for newly added tracing dependencies.

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[Copilot]

Pull request overview

Copilot reviewed 11 out of 12 changed files in this pull request and generated 3 comments.

[tammy-baylis-swi]

I don't know Rust but looks helpful!