fix(input): reduce Receiver Master pointer stalls

[swellweb]

Summary

• move input debug-file writes off the Sender main actor
• sample continuous pointer/drag/scroll diagnostics while preserving key, button and error logs
• reuse the CGEvent source used to inject receiver-master input
• make Render Matching select the HiDPI backing mode instead of the duplicate LoDPI mode
• declare Local Network and TargetBridge Bonjour access in the Sender bundle

Validation

• plutil -lint TargetBridgeSupport/Info.plist
• xcodebuild test -project TargetBridge.xcodeproj -scheme TBDisplaySender -destination "platform=macOS" -derivedDataPath .build/DerivedData (140 tests)
• make test in TargetBridge-Receiver/TBReceiverC (654 checks)

Addresses the input hot-path portion of #202, the mode-selection regression isolated in #192, and the missing macOS local-network declaration relevant to #187/#203. It does not change capture, encoding, or the wire protocol. A two-Mac Stop → Connect check remains required before release.