Live frames ride sendMessage, which is reachable-only — and phone→watch
reachability drops exactly when the user is swiping on the phone (wrist
down). A frame that failed to send was staged but never retried until a
reachability edge, and a frame lost outright desynced the run until the
next human transition — sometimes forever, since a reconnect could even
re-send the stale staged frame and yank the peer backwards.
Four fixes, symmetric on both bridges and both run screens:
- A send that fails while nominally reachable now retries with a short
backoff (a few times per staged message) instead of being swallowed.
- Receiving a frame that outranks the staged outbound one drops the
staged frame, so a reconnect re-send can't move the run backwards;
a delivery the staged frame outranks is ignored as stale.
- Every staleness comparison now tie-breaks the shared version sequence
on the frame's wall-clock anchor (LiveProgress.isNewer) — after a
lost frame both devices can mint the same version, and the later
human action must win.
- Durable repair: when the absorbed workout doc shows sets completed
beyond anything the open run screen recorded or followed, it jumps
forward to the first unfinished set's work page — a lost frame now
degrades to a briefly-stale page instead of a stuck one.
Add an ephemeral live-run presence channel (separate from the durable
iCloud progress sync) so a propped-up iPhone can mirror the Watch's
Ready → work/rest → Finish flow in real time as the user swipes.
Watch drives, phone mirrors (read-only), so there's no echo loop:
- Watch's ExerciseProgressView broadcasts a LiveProgress frame on every
phase transition (and an ended signal on leave) via sendMessage,
reachable-only — throwaway presence, never written to iCloud.
- Timers ride as wall-clock anchors (Date kept native in the WC dict to
preserve sub-second precision), so both devices count independently
off shared start times and stay in lockstep without streaming ticks.
- Phone holds a transient LiveRunState; ContentView auto-presents a
read-only LiveProgressMirrorView full-screen cover while a run is live.
Claude-Session: https://claude.ai/code/session_01SCv7zvGFcKy47KSTnTLxRe
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