Propagated sampling rates

[solnic]

This ensures that we follow the spec as described here https://develop.sentry.dev/sdk/telemetry/traces/#propagated-random-value

[codecov]

Codecov Report

❌ Patch coverage is 98.98990% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 97.42%. Comparing base (9b37693) to head (04fe927).

Files with missing lines	Patch %	Lines
sentry-ruby/lib/sentry/utils/sample_rand.rb	98.11%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2671   +/-   ##
=======================================
  Coverage   97.41%   97.42%           
=======================================
  Files         135      136    +1     
  Lines        5229     5326   +97     
=======================================
+ Hits         5094     5189   +95     
- Misses        135      137    +2     

Components	Coverage Δ
sentry-ruby	97.77% <98.98%> (+0.02%)	⬆️
sentry-rails	95.95% <ø> (-0.15%)	⬇️
sentry-sidekiq	96.57% <ø> (ø)
sentry-resque	94.44% <ø> (ø)
sentry-delayed_job	94.68% <ø> (ø)
sentry-opentelemetry	99.31% <ø> (ø)

Files with missing lines	Coverage Δ
sentry-ruby/lib/sentry-ruby.rb	99.14% <100.00%> (+<0.01%)	⬆️
sentry-ruby/lib/sentry/hub.rb	97.93% <ø> (ø)
sentry-ruby/lib/sentry/propagation_context.rb	97.40% <100.00%> (+0.91%)	⬆️
sentry-ruby/lib/sentry/transaction.rb	98.32% <100.00%> (+0.24%)	⬆️
sentry-ruby/lib/sentry/utils/sample_rand.rb	98.11% <98.11%> (ø)

... and 1 file with indirect coverage changes

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[sl0thentr0py]

logic looks perfect, nice work!

if we can avoid deduplication it would be great, but maybe I missed a reason why transaction needs its own logic. We will remove Transaction.from_sentry_trace completely in the major either way.

[sl0thentr0py]

can we not define these methods again, but add params to the ones in PropagationContext and reuse them?

so expose

• PropagationContext.extract_sample_rand_from_baggage(baggage)
• PropgationContext.generate_sample_rand(baggage, trace_id, parent_sampled)