Build, run, debug

Own the workflow with one project-local script/build_and_run.sh (never inside app source dirs). Other tools may depend on its contract.

• Default path is kill the running app, build, launch. Optional flags: --debug (lldb), --logs (stream process logs), --telemetry (unified log filtered to app subsystem), --verify (launch, then pgrep -x <AppName>).
• Xcode projects use xcodebuild. SwiftPM command-line tools launch raw.
• SwiftPM GUI apps must be staged as dist/<AppName>.app (binary in Contents/MacOS, minimal Info.plist with CFBundlePackageType=APPL, CFBundleExecutable, CFBundleIdentifier, CFBundleName, LSMinimumSystemVersion, NSPrincipalClass=NSApplication) and launched with /usr/bin/open -n. A raw executable gives no Dock icon, no activation, and bundle id warnings. If the window stays behind, check NSApp.setActivationPolicy(.regular) and NSApp.activate(ignoringOtherApps: true).
• Run git init only if the workspace is not already inside a git repo. Never nest one.
• Classify failures (compiler, linker, signing, build settings, SDK, script, runtime launch) and quote the smallest useful error. No simulator or mobile workflows on macOS. Do not claim UI state you cannot inspect.