feat: Add request start date to network breadcrumb

[brustolin]

📜 Description

💡 Motivation and Context

Needed for session replay breadcrumb (#4002).

💚 How did you test it?

Unit tests

📝 Checklist

You have to check all boxes before merging:

• I reviewed the submitted code.
• 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.
• 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.

🔮 Next steps

[github-actions]

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

Generated by 🚫 dangerJS against db6e85a

[github-actions]

🚨 Detected changes in high risk code 🚨

High-risk code can easily blow up and is hard to test. We had severe bugs in the past. Be extra careful when changing these files, and have an extra careful look at these:

• Sources/Sentry/SentryNetworkTracker.m

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.866%. Comparing base (cf97209) to head (db6e85a).
Report is 1 commits behind head on main.

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #4008       +/-   ##
=============================================
+ Coverage   90.844%   90.866%   +0.021%     
=============================================
  Files          593       593               
  Lines        46519     46564       +45     
  Branches     16633     16642        +9     
=============================================
+ Hits         42260     42311       +51     
+ Misses        4076      4072        -4     
+ Partials       183       181        -2     

Files	Coverage Δ
Sources/Sentry/SentryNetworkTracker.m	96.451% <100.000%> (+0.058%)	⬆️
...erformance/Network/SentryNetworkTrackerTests.swift	98.493% <100.000%> (+0.004%)	⬆️

... and 8 files with indirect coverage changes

---

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[github-actions]

🚨 Detected changes in high risk code 🚨

High-risk code can easily blow up and is hard to test. We had severe bugs in the past. Be extra careful when changing these files, and have an extra careful look at these:

• Sources/Sentry/SentryNetworkTracker.m

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1228.08 ms	1246.90 ms	18.82 ms
Size	21.58 KiB	632.04 KiB	610.46 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
dd4145f	1233.48 ms	1254.35 ms	20.88 ms
3cba0e8	1250.86 ms	1258.39 ms	7.53 ms
69d8759	1235.71 ms	1241.34 ms	5.63 ms
dcec216	1238.94 ms	1261.06 ms	22.12 ms
aa45f36	1226.39 ms	1253.22 ms	26.84 ms
7bb0873	1215.65 ms	1235.00 ms	19.35 ms
7fe37ab	1228.92 ms	1243.86 ms	14.94 ms
cd39d58	1203.87 ms	1239.88 ms	36.01 ms
11b2ffa	1204.86 ms	1218.16 ms	13.31 ms
c021422	1237.12 ms	1263.18 ms	26.06 ms

App size

Revision	Plain	With Sentry	Diff
dd4145f	21.58 KiB	540.09 KiB	518.51 KiB
3cba0e8	22.84 KiB	403.19 KiB	380.34 KiB
69d8759	20.76 KiB	393.05 KiB	372.29 KiB
dcec216	20.76 KiB	432.88 KiB	412.11 KiB
aa45f36	21.58 KiB	616.73 KiB	595.15 KiB
7bb0873	22.85 KiB	407.09 KiB	384.24 KiB
7fe37ab	21.58 KiB	542.28 KiB	520.70 KiB
cd39d58	20.76 KiB	435.26 KiB	414.50 KiB
11b2ffa	22.85 KiB	412.67 KiB	389.82 KiB
c021422	20.76 KiB	435.64 KiB	414.88 KiB

Previous results on branch: feat/network-breadcrumb-start

Startup times

Revision	Plain	With Sentry	Diff
e930c26	1220.94 ms	1238.76 ms	17.82 ms

App size

Revision	Plain	With Sentry	Diff
e930c26	21.58 KiB	632.13 KiB	610.55 KiB

[philipphofmann]

LGTM, with two suggestions. Thanks for putting this in an extra PR.

[github-actions]

🚨 Detected changes in high risk code 🚨

High-risk code can easily blow up and is hard to test. We had severe bugs in the past. Be extra careful when changing these files, and have an extra careful look at these:

• Sources/Sentry/SentryNetworkTracker.m