refactor: Add null-handling and tests for array sanitizing

[philprime]

This PR is derived from #5572 in an effort to make the large amount of changes easier to review for #5577.

Should be merged after #5737

Fixes nullability handling and tests for the SentryArray sanitization utilities.

#skip-changelog

[philipphofmann]

Thanks.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.707%. Comparing base (ebc72be) to head (5975a8c).
⚠️ Report is 3 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #5738       +/-   ##
=============================================
+ Coverage   86.187%   86.707%   +0.520%     
=============================================
  Files          423       423               
  Lines        36106     36172       +66     
  Branches     15246     17021     +1775     
=============================================
+ Hits         31119     31364      +245     
+ Misses        4944      4527      -417     
- Partials        43       281      +238     

Files with missing lines	Coverage Δ
Sources/Sentry/SentryArray.m	100.000% <100.000%> (ø)
Sources/Sentry/SentryNSDictionarySanitize.m	100.000% <ø> (ø)

... and 62 files with indirect coverage changes

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[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1223.16 ms	1251.57 ms	28.41 ms
Size	23.75 KiB	908.16 KiB	884.41 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
f8029e2	1245.16 ms	1261.32 ms	16.16 ms
2481950	1221.04 ms	1248.98 ms	27.94 ms
15c8cd5	1220.24 ms	1246.14 ms	25.90 ms
e64d3d4	1241.90 ms	1260.10 ms	18.20 ms
fac4ca3	1222.81 ms	1235.83 ms	13.02 ms
51f74d7	1236.31 ms	1247.43 ms	11.12 ms
5c5648e	1234.44 ms	1253.79 ms	19.35 ms
5ec90e0	1235.57 ms	1258.45 ms	22.88 ms
7148f97	1235.09 ms	1258.07 ms	22.98 ms
c63e0fe	1230.58 ms	1253.94 ms	23.35 ms

App size

Revision	Plain	With Sentry	Diff
f8029e2	23.75 KiB	893.72 KiB	869.97 KiB
2481950	23.74 KiB	872.74 KiB	849.00 KiB
15c8cd5	23.75 KiB	908.01 KiB	884.26 KiB
e64d3d4	23.75 KiB	855.37 KiB	831.62 KiB
fac4ca3	23.75 KiB	902.01 KiB	878.27 KiB
51f74d7	23.74 KiB	874.08 KiB	850.34 KiB
5c5648e	23.75 KiB	879.60 KiB	855.86 KiB
5ec90e0	23.74 KiB	872.67 KiB	848.92 KiB
7148f97	23.75 KiB	854.78 KiB	831.03 KiB
c63e0fe	23.74 KiB	874.08 KiB	850.33 KiB

Previous results on branch: philprime/strict-nullability-3

Startup times

Revision	Plain	With Sentry	Diff
dd24cb0	1239.45 ms	1262.78 ms	23.33 ms

App size

Revision	Plain	With Sentry	Diff
dd24cb0	23.75 KiB	908.20 KiB	884.45 KiB