Add a focused .swiftlint.yml (custom rules only, no default style noise) flagging
raw String(localized:) / LocalizedStringKey / systemName|systemImage literals, and
wire it as a required pre-build phase that fails the build if SwiftLint is missing
(brew install swiftlint). The phase prepends the Homebrew bin dirs since Xcode runs
scripts with a minimal PATH. Runs clean on the current tree (0 violations).
