Fix path callback Swift name

[Kyle-Ye]

Summary

Fix the Swift importer name for path callback flags by using the valid nested type name ORBPath.CallbacksFlags instead of the unsupported ORBPath.Callbacks.Flags spelling.

This keeps the callback flag type named for Swift users instead of leaving it as a plain C import, and updates the non-CoreGraphics fallback Swift declarations to match the imported API shape.

Root Cause

The Swift importer accepts the ORBPath.Callbacks record mapping, but rejects the deeper ORBPath.Callbacks.Flags record name and reports an invalid base identifier warning.

Validation

• Typechecked OpenRenderBox.h through swiftc -typecheck -import-objc-header and verified ORBPath.CallbacksFlags imports without the warning.
• Built OpenSwiftUI with local dependencies enabled:
  OPENSWIFTUI_USE_LOCAL_DEPS=1 OPENRENDERBOX_USE_LOCAL_DEPS=1 OPENATTRIBUTEGRAPH_USE_LOCAL_DEPS=1 swift build --target OpenSwiftUI
• Confirmed the local-dependency build log has no Callbacks.Flags or invalid swift_name warning matches.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 0.00%. Comparing base (38d099f) to head (db46982).

Files with missing lines	Patch %	Lines
Sources/OpenRenderBox/Path/ORBPathCallbacks.swift	0.00%	12 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main     #28   +/-   ##
=====================================
  Coverage   0.00%   0.00%           
=====================================
  Files          8       8           
  Lines        356     356           
=====================================
  Misses       356     356           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.