v9: Parent-child relationship for the PlatformExceptions and Cause

[denrase]

📜 Description

• Introduce child relationships (exceptions) in SentryExceptions, so we can preserve nested relationships.
• Flatten exceptions into list with ids and parent references according to RFC.

💡 Motivation and Context

Closes #1859

💚 How did you test it?

📝 Checklist

• I reviewed submitted code
• I added tests to verify changes
• No new PII added or SDK only sends newly added PII if sendDefaultPii is enabled
• I updated the docs if needed
• All tests passing
• No breaking changes

🔮 Next steps

[github-actions]

	Fails
🚫	Please consider adding a changelog entry for the next release.

Instructions and example for changelog

Please add an entry to CHANGELOG.md to the "Unreleased" section. Make sure the entry includes this PR's number.

Example:

## Unreleased

- Parent-child relationship for the PlatformExceptions and Cause ([#2803](https://github.com/getsentry/sentry-dart/pull/2803))

If none of the above apply, you can opt out of this check by adding #skip-changelog to the PR description.

Generated by 🚫 dangerJS against 9a23c4a

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.57%. Comparing base (0c06a7d) to head (9a23c4a).

❗ There is a different number of reports uploaded between BASE (0c06a7d) and HEAD (9a23c4a). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (0c06a7d)	HEAD (9a23c4a)
	9	7

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2803       +/-   ##
===========================================
- Coverage   88.60%   78.57%   -10.03%     
===========================================
  Files         263       34      -229     
  Lines        8766     1377     -7389     
===========================================
- Hits         7767     1082     -6685     
+ Misses        999      295      -704     

☔ View full report in Codecov by Sentry.
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[github-actions]

Android Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	453.27 ms	521.45 ms	68.18 ms
Size	6.44 MiB	7.56 MiB	1.12 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
d10745a	318.86 ms	374.82 ms	55.96 ms
1b0c8a3	479.78 ms	521.18 ms	41.40 ms
824df58	436.68 ms	548.80 ms	112.12 ms
e6b16cd	523.24 ms	594.77 ms	71.53 ms
9f9f94f	331.04 ms	368.92 ms	37.88 ms
3392f27	486.67 ms	629.35 ms	142.68 ms
5aab4c5	326.12 ms	378.82 ms	52.70 ms
abcdba3	354.68 ms	399.04 ms	44.36 ms
32fa6b6	420.38 ms	497.90 ms	77.52 ms
b9da046	393.00 ms	455.52 ms	62.52 ms

App size

Revision	Plain	With Sentry	Diff
d10745a	6.26 MiB	7.20 MiB	956.08 KiB
1b0c8a3	6.49 MiB	7.57 MiB	1.08 MiB
824df58	6.35 MiB	7.35 MiB	1021.71 KiB
e6b16cd	6.35 MiB	7.33 MiB	1005.63 KiB
9f9f94f	5.94 MiB	6.95 MiB	1.01 MiB
3392f27	6.46 MiB	7.48 MiB	1.02 MiB
5aab4c5	6.06 MiB	7.10 MiB	1.04 MiB
abcdba3	5.94 MiB	6.95 MiB	1.01 MiB
32fa6b6	6.35 MiB	7.35 MiB	1021.69 KiB
b9da046	6.06 MiB	7.03 MiB	990.30 KiB

Previous results on branch: enha/rel-platfomr-cause

Startup times

Revision	Plain	With Sentry	Diff
b950043	444.28 ms	505.20 ms	60.91 ms
2e189f2	526.22 ms	550.76 ms	24.54 ms

App size

Revision	Plain	With Sentry	Diff
b950043	6.44 MiB	7.56 MiB	1.12 MiB
2e189f2	6.44 MiB	7.56 MiB	1.12 MiB

[github-actions]

iOS Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1260.02 ms	1282.49 ms	22.47 ms
Size	8.43 MiB	9.98 MiB	1.55 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
22ed6cb	1277.41 ms	1283.76 ms	6.35 ms
d4120ac	1260.61 ms	1274.09 ms	13.47 ms
19a9adb	1249.21 ms	1258.31 ms	9.09 ms
b39b48c	1229.22 ms	1255.17 ms	25.95 ms
ccc09e4	1254.74 ms	1277.08 ms	22.34 ms
1edf30e	1254.43 ms	1272.82 ms	18.39 ms
b2cbbc8	1240.00 ms	1254.37 ms	14.37 ms
bd1b990	1209.43 ms	1226.96 ms	17.53 ms
8a7f528	1232.57 ms	1249.82 ms	17.24 ms
691aa3b	1265.57 ms	1282.13 ms	16.55 ms

App size

Revision	Plain	With Sentry	Diff
22ed6cb	8.10 MiB	9.17 MiB	1.08 MiB
d4120ac	8.28 MiB	9.34 MiB	1.06 MiB
19a9adb	8.42 MiB	9.86 MiB	1.44 MiB
b39b48c	8.42 MiB	9.91 MiB	1.48 MiB
ccc09e4	8.16 MiB	9.16 MiB	1.01 MiB
1edf30e	8.16 MiB	9.17 MiB	1.01 MiB
b2cbbc8	8.10 MiB	9.18 MiB	1.08 MiB
bd1b990	8.32 MiB	9.38 MiB	1.06 MiB
8a7f528	8.10 MiB	9.16 MiB	1.06 MiB
691aa3b	8.16 MiB	9.17 MiB	1.01 MiB

Previous results on branch: enha/rel-platfomr-cause

Startup times

Revision	Plain	With Sentry	Diff
b950043	1257.96 ms	1280.29 ms	22.33 ms
2e189f2	1250.57 ms	1277.29 ms	26.71 ms

App size

Revision	Plain	With Sentry	Diff
b950043	8.43 MiB	9.98 MiB	1.55 MiB
2e189f2	8.43 MiB	9.98 MiB	1.55 MiB