fix: Async safe log for backtrace in CPPException

[philipphofmann]

📜 Description

Use async safe logging when getting the backtrace for CPP Exceptions. When an unhandled CPPExceptions occurs, the crash monitor for CPPExceptions uses SentryCrashStackCursor_SelfThread, which uses non async safe SenryLog. This is fixed now by using async safe logging in SentryCrashStackCursor_SelfThread. Only users using debug = true or setting the log level to debug were impacted by this issue.

💡 Motivation and Context

Came up while investigating #4226.

💚 How did you test it?

Unit tests are still green.

📝 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.

[philprime]

LGTM!

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1221.59 ms	1260.29 ms	38.69 ms
Size	22.30 KiB	848.26 KiB	825.95 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
f25febb	1209.08 ms	1225.90 ms	16.81 ms
2337de8	1227.42 ms	1236.61 ms	9.19 ms
1bbcb9c	1214.25 ms	1230.04 ms	15.79 ms
e324230	1230.59 ms	1248.20 ms	17.61 ms
c0b4b71	1218.16 ms	1251.28 ms	33.12 ms
92d1dc2	1226.92 ms	1246.02 ms	19.10 ms
bb7da60	1231.80 ms	1252.65 ms	20.85 ms
7afad57	1216.52 ms	1245.59 ms	29.07 ms
5eb5b30	1227.06 ms	1243.47 ms	16.41 ms
e2484ac	1236.94 ms	1257.82 ms	20.88 ms

App size

Revision	Plain	With Sentry	Diff
f25febb	21.58 KiB	414.92 KiB	393.34 KiB
2337de8	22.31 KiB	818.67 KiB	796.36 KiB
1bbcb9c	20.76 KiB	426.10 KiB	405.34 KiB
e324230	22.85 KiB	408.87 KiB	386.02 KiB
c0b4b71	20.76 KiB	430.98 KiB	410.22 KiB
92d1dc2	22.30 KiB	844.42 KiB	822.11 KiB
bb7da60	21.58 KiB	697.84 KiB	676.25 KiB
7afad57	22.30 KiB	832.29 KiB	809.99 KiB
5eb5b30	22.30 KiB	823.44 KiB	801.13 KiB
e2484ac	22.31 KiB	768.19 KiB	745.87 KiB

Previous results on branch: fix/async-safe-logging-cpp-backtrace

Startup times

Revision	Plain	With Sentry	Diff
97d6703	1216.18 ms	1240.85 ms	24.67 ms

App size

Revision	Plain	With Sentry	Diff
97d6703	22.30 KiB	847.84 KiB	825.53 KiB

[codecov]

Codecov Report

Attention: Patch coverage is 91.66667% with 2 lines in your changes missing coverage. Please review.

Project coverage is 92.789%. Comparing base (03fd0bb) to head (3e76db2).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ecording/Tools/SentryCrashStackCursor_SelfThread.m	60.000%	2 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #5098       +/-   ##
=============================================
- Coverage   92.789%   92.789%   -0.001%     
=============================================
  Files          675       676        +1     
  Lines        83865     83877       +12     
  Branches     30553     30531       -22     
=============================================
+ Hits         77818     77829       +11     
+ Misses        5950      5947        -3     
- Partials        97       101        +4     

Files with missing lines	Coverage Δ
...yCrash/SentryCrashStackCursorSelfThreadTests.swift	100.000% <100.000%> (ø)
...ecording/Tools/SentryCrashStackCursor_SelfThread.m	88.461% <60.000%> (ø)

... and 17 files with indirect coverage changes

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