Replace the free-form InvitationError.message(String) case with semantic
cases mapped to L10n keys at the UI boundary (Error.uiText), so user-facing
error text is localized instead of substring-matched from English blobs.
.raw(String) remains only for genuinely dynamic system/core messages.
Localize the CoreNFC alertMessage prompts via existing L10n keys, and add
SwiftLint rules (raw_alert_message, raw_invitation_error) to catch raw
alert strings and literal .raw("…") errors going forward.
The typed-resource rules missed a bare string literal passed as the leading arg of
a view initializer (e.g. Label("send_stop_sharing", …)), which is an implicit
LocalizedStringKey. Add a rule covering Text/Label/Button/Section/Picker/etc.
(empty labels allowed). Fixes the two dynamic-content Text sites it surfaced by
switching them to Text(verbatim:).
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).
