feat(watch): add lap detection via accelerometer and workout sync to phone

src/db/operations.ts

@@ -135,6 +135,51 @@ export async function getWorkoutLaps(workoutId: string) {
   return db.select().from(laps).where(eq(laps.workoutId, workoutId));
 }
 
+export async function saveWatchCompletedWorkout(data: {
+  workoutId: string;
+  duration: number;
+  totalDistance: number;
+  calories: number;
+  laps: Array<{
+    setPosition: number;
+    repNumber: number;
+    distance: number;
+    duration: number;
+    heartRate: number;
+  }>;
+}) {
+  const avgHeartRate =
+    data.laps.length > 0
+      ? Math.round(data.laps.reduce((sum, l) => sum + (l.heartRate || 0), 0) / data.laps.length)
+      : 0;
+
+  await db
+    .update(workouts)
+    .set({
+      finishedAt: new Date().toISOString(),
+      totalDuration: data.duration,
+      totalDistance: data.totalDistance || 0,
+      calories: data.calories || 0,
+      avgHeartRate,
+      source: "watch",
+    })
+    .where(eq(workouts.id, data.workoutId));
+
+  for (const lap of data.laps) {
+    await db.insert(laps).values({
+      id: generateUUID(),
+      workoutId: data.workoutId,
+      setPosition: lap.setPosition,
+      repNumber: lap.repNumber,
+      distance: lap.distance,
+      duration: lap.duration,
+      heartRate: lap.heartRate || null,
+      strokeCount: null,
+      swolf: null,
+    });
+  }
+}
+
 // ─── Stats ───────────────────────────────────────────────────
 
 export async function getWeeklyStats() {

src/features/watch-connectivity/hooks/useWatchWorkoutSync.ts

@@ -0,0 +1,36 @@
+import { useEffect, useRef } from "react";
+import WatchConnectivity from "../../../modules/watch-connectivity";
+import { saveWatchCompletedWorkout } from "@db/operations";
+
+export function useWatchWorkoutSync() {
+  const pollingRef = useRef<ReturnType<typeof setInterval> | null>(null);
+
+  useEffect(() => {
+    pollingRef.current = setInterval(async () => {
+      try {
+        const events = (await WatchConnectivity.pollEvents()) as any[];
+        for (const event of events) {
+          if (event.type === "workoutCompleted") {
+            console.log("[useWatchWorkoutSync] Received workoutCompleted:", event.workoutId);
+            await saveWatchCompletedWorkout({
+              workoutId: event.workoutId,
+              duration: event.duration ?? 0,
+              totalDistance: event.totalDistance ?? 0,
+              calories: event.calories ?? 0,
+              laps: event.laps ?? [],
+            });
+            console.log("[useWatchWorkoutSync] Saved completed workout to DB");
+          }
+        }
+      } catch (error) {
+        // Silently ignore polling errors
+      }
+    }, 2000);
+
+    return () => {
+      if (pollingRef.current) {
+        clearInterval(pollingRef.current);
+      }
+    };
+  }, []);
+}