Fix @MainActor warnings for startRunning/stopRunning#174
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Add strict-concurrency compiler flag and mark ScannerViewController as @mainactor. Remove DispatchQueue.global dispatches around AVCaptureSession.startRunning() and stopRunning() which are @mainactor isolated in modern Swift, eliminating concurrency warnings reported in issue twostraws#105. Fixes twostraws#105
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Summary
Fix the @mainactor concurrency warnings reported in #105.
Changes
Package.swift-strict-concurrency=targetedcompiler flag viaunsafeFlagsto enable strict concurrency checking for the target.ScannerViewController.swiftScannerViewControllerwith@MainActor.DispatchQueue.global(qos: .userInteractive).asyncwrappers aroundcaptureSession.startRunning()andcaptureSession.stopRunning()-- these methods are@MainActor-isolated in modern Swift, so dispatching them to a background queue triggers concurrency warnings. Calling them directly on the main thread is the correct approach.Why this fix
AVCaptureSession.startRunning()andstopRunning()are@MainActormethods. The previous implementation dispatched them to a background queue (DispatchQueue.global), which triggers concurrency warnings when strict concurrency checking is enabled. By markingScannerViewControlleras@MainActorand calling these methods directly on the main thread, the warnings are eliminated and thread safety is guaranteed.Fixes #105