`NavigationSuiteScaffold` gives the bar on a phone and the rail on a wide
layout from one declaration. Each tab keeps its own back stack; re-selecting
a tab returns to its root, and predictive back is wired only where back
actually goes somewhere.
The pill is the running-state surface from PLAN §9: it floats above the bar,
speaks for whichever subject is closest to needing attention, and pauses or
stops it from any tab. Its callbacks are gated on a live subject, so a second
tap during its exit animation cannot restart a timer the user just reset.
The notification permission is asked once, and the flag is written from the
request's result rather than before it — a process death mid-dialog leaves
the ask due again rather than recorded and never made. Three tabs are empty
shells until M5 through M8 fill them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wmy1BpCKi8KeSjaWhYuCPV