feat: Implement OpenTelemetry tracing

[iamKunalGupta]

• Add basic telemetry and examples
• Integrate with temporal's opentelemetry interceptor

To run/test:

1. Run jaeger (it supports otlp format ingestion with a nice UI):

   docker run --rm --name jaeger -p 16686:16686 -p 4317:4317 -e JAEGER_REPORTER_LOG_SPANS=true -e JAEGER_SAMPLER_TYPE=const -e JAEGER_SAMPLER_PARAM=1 -e COLLECTOR_OTLP_ENABLED=true jaegertracing/all-in-one:1.57

   Open jaeger ui at http://localhost:16686/
2. Run flow worker with the following env:

   ENABLE_OTEL_TRACING=true
   OTEL_EXPORTER_OTLP_TRACES_PROTOCOL=grpc
   OTEL_EXPORTER_OTLP_TRACES_ENDPOINT=http://localhost:4317

Start any activity etc and we should start seeing traces like below:

TODOS:

• add tracing to grpc+gateway

[serprex]

avoid creating many small packages, it doesn't really matter until intersubpackage dependencies get involved. go's naming also makes having common names like util, utils, common, etc a pain

Already had to resolve util/utils split

[iamKunalGupta]

the call graph is like setup -> tracing/metrics/logging -> common, so had to create a separate one this time.
I'll also change it to otel_common for better visibility

[serprex]

can move this into GetAs, using reflect.TypeFor[T] to put T in span label

[CLAassistant]

All committers have signed the CLA.

[heavycrystal]

is this tool generated?

[iamKunalGupta]

weird