* fix(mobile-ios): pin fastlane and gate the Fastfile in CI
The ios-distribute job failed on every run from 2026-08-10 to 2026-08-13
because distribute_testflight passed distribute_only without app_platform,
so pilot fell through to an interactive platform prompt on ubuntu. No CI
check loads the Fastfile, so external testers got nothing for six days.
- Pin fastlane 2.238.0 and commit mobile/Gemfile.lock so ios-build (macos)
and ios-distribute (ubuntu) cannot resolve different versions ~25 minutes
apart. Fixes the Gemfile comment's dead mobile-build.yml reference.
- Add a Fastfile smoke check (bundle exec fastlane lanes) plus a static
contract test for the TestFlight lane arguments to Mobile Checks.
- Set reject_build_waiting_for_review so a superseded same-train build in
beta review stops blocking the submission.
* fix(mobile-ios): install the pinned Gemfile.lock in frozen mode
Without frozen, a lockfile that drifts from the Gemfile is silently
re-resolved per job, which is the version split the pin exists to prevent.
* test(mobile-ios): anchor the TestFlight argument contract against an empty selection
* chore(mobile-ios): canonicalize the lockfile platforms
Bundler's own normalization drops arm64-darwin-25 as redundant with the
versionless arm64-darwin, and the ubuntu runners resolve x86_64-linux-gnu.
