Missing support for FileSystemSynchronizedGroup

[iorecicSA]

Describe the bug
When running periphery scan on project containting FileSystemSynchronizedGroup I get the following error:
Error: (Error) unknownName("FileSystemSynchronizedGroup")

Reproduction
If you are reporting an incorrect result, please provide a sample Xcode or Swift package project that reproduces the issue.

Environment
Copy the output from running:

periphery version 
3.7.2

swift -version 
swift-driver version: 1.148.6 Apple Swift version 6.3 (swiftlang-6.3.0.123.5 clang-2100.0.123.102)
Target: arm64-apple-macosx26.0

xcodebuild -version
Xcode 26.4
Build version 17E192