Add basic tracing to Cloudflare Workers

[thaddeus]

Adds auto and manual instrumentation to the cloudflare workers.

A tracer is initialized by reading the OTEL_ENDPOINT environment variable, which tells the tracer where to send the processed results.

When the worker is triggered, a new trace operation is started automatically by the instrument call in main.js. First, the head sampler determines if the request should be actually sampled and logged, using the ratio value. Ratio can be set by setting a TRACE_RATIO environment variable to a value between 0 (never) and 1 (always). By default, production will sample 0.05 (5%) of the requests from there it automatically instruments things like fetch calls, and KV loads. Non-production environments will default to 1.0 (100%) sample rates.

All traces are set to tag the traces with a service name of tarkov-api, a namespace of tarkov-dev.{ENVIRONMENT}, and a version of {TAPI_COMMIT_REF} (intended to be set on deploy), falling back to unknown.

Several methods of some interest have been manually instrumented, by wrapping them in the tracer.startActiveSpan call. Each instrumented span will record the duration the function took to execute. Spans can have attributes and events associated with them, to add extra details for analysis and debugging.

Important note: To make this possible, I had to remove the node_compat flag, and replace it with nodejs_compat - this does require some care when integrating with some libraries that don't support the node: prefix for built-in packages

[github-actions]

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[GrantBirki]

1.  AssertionError  correct item shortName                      
                     expected 'Car battery' to equal 'Car batt.' 
                     at assertion:5 in test-script               
                     inside "Item by Name - Detailed"

Well that is odd 🤔 logs

[GrantBirki]

Looks like the short name changed

[thaddeus]

Closing as outdated