feat(usage-metrics-dashboard): wire up to send otel signals [DRAFT]

[toph-allen]

Instruments the Usage Metrics Dashboard to send OTel signals if its environment is configured appropriately. To learn more about required environment variables, see Collecting Telemetry Data docs for R's otelsdk package.

• Uses the otel package to manually track spans in certain functions, as well as app initialization.
• Uses a dev version of Shiny 1.2.0, which supports auto-instrumentation for all reactive operations.
• Note that sending instrumentation requires the otelsdk R package, which has a dependency on the protobuf binary, so this version of the content won't run on a Connect server without that binary installed.

[jonkeane]

Note that sending instrumentation requires the otelsdk R package, which has a dependency on the protobuf binary, so this version of the content won't run on a Connect server without that binary installed.

Oh how I wish we had a private / dev feed of our extensions we could use for circumstances like this.