Import selected LookinServer stability fixes

[nova286]

Summary

• import the iOS 18 maskView collision fix from [fix] 修复 Xcode16 编译， 在 iOS18 无法进行 UI Debug 的问题。 主要是由于 maskView 属性跟系统同名了。 QMUI/LookinServer#159
• disable LookinServer startup inside SwiftUI Previews based on chore: 在 SwiftUI Previews 模式中不启用 QMUI/LookinServer#165
• handle null Peertalk payloads based on fix: data在锁屏状态下可能为nil QMUI/LookinServer#173
• document original pull requests, commits, authors, and local adaptations

Local adaptations

• the Preview guard uses an early return instead of an empty branch
• a null dispatch payload is treated as zero bytes so the existing completion and error callbacks still run

Validation

• git diff --check origin/master...HEAD
• xcodebuild -scheme LookinServer -destination 'generic/platform=iOS Simulator' -configuration Debug -derivedDataPath /tmp/LookinServerCommunityFixesDerivedData CODE_SIGNING_ALLOWED=NO build -quiet

The build completed successfully. Existing NSKeyedArchiver and NSKeyedUnarchiver deprecation warnings remain unchanged.