Docs and CHANGELOG reference telemetry env vars/flags the code doesn't read

[Dominik1999]

Severity: medium (documentation).

Summary

Operator docs (docs/src/operator/monitoring.md:5-7,78-84, docs/external/src/operators.md:55-60) document OTEL_ENABLED / OTEL_TRACES_ENDPOINT, but the code only reads OTEL_EXPORTER_OTLP_TRACES_ENDPOINT / OTEL_EXPORTER_OTLP_ENDPOINT (crates/node/src/logging.rs:41-50). The CHANGELOG (v0.4.1) additionally claims --enable-otel/--otel-endpoint CLI flags that do not exist (bin/node/src/main.rs:11-39).

Impact

An operator following the published docs gets zero telemetry, silently — compounded by the exporter build error being swallowed at logging.rs:96 (a malformed endpoint disables tracing with no log).

Recommendation

Fix both doc trees and the changelog to the actual OTEL_EXPORTER_OTLP_* variables; log a warning (or fail startup) when an explicitly-requested OTEL exporter fails to build.

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Part of #114.

[mehmetkr-31]

I'd like to take this one. Opened a draft PR fixing both doc trees and the changelog entry, and logging the swallowed exporter build error.

Worth noting the changelog entry was wrong in a second way beyond the env vars: it also claimed --enable-otel/--otel-endpoint CLI flags, and the binary has never had any telemetry flags at all.

[kutluhaneth46]

Docs still document OTEL_ENABLED / OTEL_TRACES_ENDPOINT while the node only reads OTEL_EXPORTER_OTLP_*. Taking this to fix both doc trees and the changelog claim about CLI flags, plus a warning when the exporter fails to build.