fix(UNTRACKED): support "none" value for OTEL exporters to disable telemetry

[micmarty-deepsense]

Problem

When OTEL_TRACES_EXPORTER=none or OTEL_METRICS_EXPORTER=none is set, plugin pods crash on startup with:

Real-world scenario

In in-vpc or single-node clusters, you might notice this issue in plugin pods (created by the job-execution-operator) when you set those environment variables in the JOB_ENV_VARS block.

https://github.com/Unstructured-IO/platform-applications-cd/blob/9cf7335f3fe620106c61da208c12d44539d743bc/apps/dataplane/etl-operator/values.yaml#L52

NotImplementedError: none implementation not supported yet

Root cause: The code splits the env var by comma but doesn't filter "none", then tries to initialize exporters for it, hitting the NotImplementedError in _add_trace_exporter() and _get_metrics_reader().

Solution

1. Filter "none" from exporter lists (lines 33, 37)

trace_exporters = [e for e in trace_exporters if e != "none"]
metric_exporters = [e for e in metric_exporters if e != "none"]

2. Return None when no exporters configured (lines 45-49, 59-63)

def get_trace_provider() -> TracerProvider | None:
    settings = get_settings()
    if not settings["trace_exporters"]:
        return None  # Let OTEL SDK use default no-op
    ...

Compatibility

FastAPIInstrumentor.instrument_app() explicitly supports None values for tracer_provider and meter_provider parameters (defaults to None). When None, OTEL SDK uses its built-in no-op providers.

Testing

Before: Plugin crashes with NotImplementedError
After: Plugin starts successfully with telemetry disabled

Changes

• Filter "none" from OTEL_TRACES_EXPORTER and OTEL_METRICS_EXPORTER env vars
• Return None from get_trace_provider/get_metric_provider when exporters list empty
• Bump version 0.0.41 → 0.0.42
• Update CHANGELOG.md

Deployment

1. After merge, we need to rebuild platform-plugins images (auto-picks latest version)
2. Cut a new platform release