SwiftPM warning control settings supported

PackageInfo decoding now understands the SwiftPM target build-setting kinds treatAllWarnings, treatWarning, and enableWarning, and Tuist maps them to the same flags SwiftPM itself emits. Swift controls land in OTHER_SWIFT_FLAGS (-warnings-as-errors / -no-warnings-as-errors for treatAllWarnings and -Werror / -Wwarning for treatWarning). C and C++ controls land in OTHER_CFLAGS / OTHER_CPLUSPLUSFLAGS (-Werror / -Wno-error for treatAllWarnings, -Werror= / -Wno-error= for treatWarning, and -W for enableWarning). Packages that use these newer SwiftPM APIs (for example Point-Free’s swift-dependencies 1.13.0) now decode and generate Xcode projects that preserve the package author’s warning behaviour.