feat(render): add view blend modes

[Kyle-Ye]

Summary

• Add view modifiers and renderer effects for public, extended, and graphics blend modes.
• Apply QuartzCore compositing filters and support conversion between filter names and RenderBox blend modes.
• Add a shared example, snapshot coverage for all 21 public modes, and shim tests for mappings and fallback values.
• Update the DPF and ORB revisions to the merged blend mode declarations.

All 21 snapshot cases passed against SwiftUI references on iOS 18.5. Both native ORB and Apple header paths passed 108 focused shim cases.

Stack

Depends on #1126.

Dependency

• DarwinPrivateFrameworks#74 (merged)
• OpenRenderBox#32 (merged)

[codecov]

Codecov Report

❌ Patch coverage is 0% with 17 lines in your changes missing coverage. Please review.
✅ Project coverage is 26.41%. Comparing base (631bf3b) to head (0d11757).

Files with missing lines	Patch %	Lines
...UICore/Render/RendererEffect/BlendModeEffect.swift	0.00%	16 Missing ⚠️
...urces/OpenSwiftUICore/Graphic/GraphicsFilter.swift	0.00%	1 Missing ⚠️

Additional details and impacted files

@@                         Coverage Diff                          @@
##           feature/effect-compositing-group    #1127      +/-   ##
====================================================================
- Coverage                             30.79%   26.41%   -4.39%     
====================================================================
  Files                                   877      818      -59     
  Lines                                 70864    61556    -9308     
====================================================================
- Hits                                  21825    16259    -5566     
+ Misses                                49039    45297    -3742     

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[tuist]

🛠️ Tuist Run Report 🛠️

Tests 🧪

Scheme	Status	Ran test modules	Commit
OpenSwiftUI	✅	7	db66e46cc

Builds 🔨

Scheme	Status	Duration	Commit
OpenSwiftUI	✅	58.5s	db66e46cc

[Kyle-Ye]

/uitest all osui-iag update only-testing=OpenSwiftUIUITests/BlendModeEffectUITests