fix(build): avoid UIKit indexing crashes on iOS

[Kyle-Ye]

Summary

• Extend the Swift 6.3.3 system-module indexing workaround to iOS to avoid UIKit deserialization crashes during builds.
• Keep source indexing enabled on iOS and macOS.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 29.75%. Comparing base (0e5fb9d) to head (9b8615b).

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1053       +/-   ##
===========================================
+ Coverage   17.11%   29.75%   +12.63%     
===========================================
  Files         735      783       +48     
  Lines       53937    61659     +7722     
===========================================
+ Hits         9234    18348     +9114     
+ Misses      44703    43311     -1392     

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[tuist]

🛠️ Tuist Run Report 🛠️

Tests 🧪

Scheme	Status	Cache hit rate	Tests	Skipped	Ran	Commit
OpenSwiftUI	✅	0 %	1161	0	1161	e2b43e266

Builds 🔨

Scheme	Status	Duration	Commit
OpenSwiftUI	✅	1m 1s	e2b43e266