[t-regbs]

Fix recurring CI setup failures and iOS verification failures while preserving the existing assertions and coverage.

• Pin Python tooling to Ubuntu 24.04 so Python 3.9 can install, and retry transient partial Android SharedPreferences snapshots with regression coverage.
• Correct iPad navigation-bar targeting, native switch interaction, and Maestro delete/undo selectors. Wait for keyboard layout before locating the Clear control.
• Use a shared reference timestamp for rendered countdown fixtures and exact assertions; production keeps its live clock. Preserve editor errors until an explicit alert action consumes them.
• Give destination rendering and cold system share-sheet presentation bounded settling time while retaining readiness predicates and improving timeout diagnostics.
• Run Maestro on a fresh simulator so XCTest's AlarmKit authorization cannot leak into permission-denial checks. Assert that denial retains the actual editor and Save control; record and clean up both simulators.

Validation:

• 33 Python script regressions plus renderer, localization, and release source gates pass on Python 3.9 and 3.14.
• Full local iPad XCTest suite passes: 19 integration tests and 10 UI tests, with one existing permission-based skip.
• Full pinned Maestro 2.10.0 suite passes on fresh iPhone and iPad simulators, including permission denial, sharing, keyboard, navigation, CRUD/undo, and sound selection.
• All nine iPad presentation locales and capture-completeness checks pass.
• Mounted production journey passes three fresh-process runs after the alert fix and three repeated runs after the share-sheet fix. The normal mounted-journey → list UI sequence passes on an erased iPad.
• Debug/Release device and simulator packaging and the Release archive pass locally with Xcode 27.2. Hosted CI uses pinned Xcode 27.0.
• All six hosted CI jobs pass on commit 455e8bd: successful CI run. This includes the full iPhone and iPad pipelines, Android build/tests and delivery verification, and both Python versions.