feat: Allow Hybrid SDKs to setTrace

[bitsandfoxes]

📜 Description

This PR allows Hybrid SDKs to explicitly set the PropagationContext on the scope via the PrivateSentrySDKOnly.

💡 Motivation and Context

The basic idea is that the Cocoa SDK, when brought in via a Hybrid SDK, should accept a trace from the Head SDK to connect errors on all layers of the application. This PR makes use of the fact that the Hybrid SDKs rely on their own performance instrumentation right now, allowing us to leverage the propagation context to achieve this.

Originates from the Unity SDK: getsentry/sentry-unity#1998
Unblocks the React Native SDK: getsentry/sentry-react-native#3918
Mirror-PR on the Java SDK: getsentry/sentry-java#4137

💚 How did you test it?

📝 Checklist

You have to check all boxes before merging:

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

#skip-changelog

[github-actions]

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against d605f92

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1233.11 ms	1249.10 ms	15.99 ms
Size	22.30 KiB	847.84 KiB	825.54 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
c59914b	1342.08 ms	1375.73 ms	33.65 ms
89491ad	1222.12 ms	1231.96 ms	9.83 ms
fc163f5	1198.05 ms	1227.76 ms	29.71 ms
e324230	1230.35 ms	1236.45 ms	6.10 ms
983de17	1260.57 ms	1263.68 ms	3.11 ms
1ce939e	1222.22 ms	1243.26 ms	21.04 ms
a9ac2b2	1241.22 ms	1256.50 ms	15.28 ms
6d541bc	1223.06 ms	1242.38 ms	19.32 ms
8f397a7	1230.10 ms	1253.88 ms	23.77 ms
9f57953	1232.83 ms	1249.87 ms	17.04 ms

App size

Revision	Plain	With Sentry	Diff
c59914b	21.58 KiB	671.90 KiB	650.32 KiB
89491ad	21.58 KiB	417.89 KiB	396.30 KiB
fc163f5	20.76 KiB	436.30 KiB	415.54 KiB
e324230	22.85 KiB	408.87 KiB	386.02 KiB
983de17	22.84 KiB	403.19 KiB	380.34 KiB
1ce939e	22.85 KiB	412.98 KiB	390.13 KiB
a9ac2b2	21.58 KiB	631.19 KiB	609.61 KiB
6d541bc	21.58 KiB	616.71 KiB	595.13 KiB
8f397a7	20.76 KiB	420.55 KiB	399.79 KiB
9f57953	22.31 KiB	773.84 KiB	751.53 KiB

Previous results on branch: feat/hybrid-sdk-set-trace

Startup times

Revision	Plain	With Sentry	Diff
d88b671	1210.06 ms	1230.88 ms	20.82 ms
ce2eef8	1220.65 ms	1242.49 ms	21.84 ms
921c24c	1216.94 ms	1239.98 ms	23.04 ms

App size

Revision	Plain	With Sentry	Diff
d88b671	22.30 KiB	846.64 KiB	824.33 KiB
ce2eef8	22.30 KiB	847.83 KiB	825.53 KiB
921c24c	22.30 KiB	846.63 KiB	824.32 KiB

[codecov]

Codecov Report

Attention: Patch coverage is 86.04651% with 6 lines in your changes missing coverage. Please review.

Project coverage is 92.738%. Comparing base (92d1dc2) to head (d605f92).
Report is 19 commits behind head on main.

Files with missing lines	Patch %	Lines
Sources/Sentry/PrivateSentrySDKOnly.mm	0.000%	6 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #5081       +/-   ##
=============================================
+ Coverage   92.720%   92.738%   +0.018%     
=============================================
  Files          674       675        +1     
  Lines        83522     83719      +197     
  Branches     30443     30488       +45     
=============================================
+ Hits         77442     77640      +198     
  Misses        5981      5981               
+ Partials        99        98        -1     

Files with missing lines	Coverage Δ
Sources/Sentry/SentryPropagationContext.m	100.000% <100.000%> (ø)
Sources/Sentry/SentryScope.m	96.990% <100.000%> (+0.078%)	⬆️
Tests/SentryTests/SentryScopeSwiftTests.swift	99.152% <100.000%> (+0.019%)	⬆️
Sources/Sentry/PrivateSentrySDKOnly.mm	23.222% <0.000%> (-0.680%)	⬇️

... and 20 files with indirect coverage changes

---

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[philprime]

Please add tests for the SentryPropagationContext.initWithTraceId to ensure that the traceId and spanId is actually set and not falling back to randomly generated ones (could be annoying to debug).

[philprime]

Almost LGTM, please add a final test case and this should be ready for merge

[philprime]

LGTM, thanks for the addition 🎉