Fix rebucketing, seed upgrades, watch pruning, end re-stamping; add model tests

Editing a workout's start date now removes the file at its old month
bucket so the record no longer duplicates on the next reconcile. Seed
reconcile re-checks the tombstone veto before overwriting an upgraded
seed. The watch applies authoritative-empty pushes so remote deletes
prune, and a re-saved finished workout keeps its original end time.
Adds unit tests for the mappers, path bucketing, and status machine.

Claude-Session: https://claude.ai/code/session_01HJDQQDA9QdP8zByg43H5v3

Workouts/Resources/StarterSplits/Bodyweight Core.split.json

@@ -77,9 +77,9 @@
       "durationSeconds" : 0,
       "id" : "01DXF6DT00MJH9N622QTMM7XB3",
       "loadType" : 0,
-      "name" : "Bird Dog",
+      "name" : "Crunch",
       "order" : 7,
-      "reps" : 8,
+      "reps" : 12,
       "sets" : 3,
       "weight" : 0
     },

Workouts/Sync/SyncEngine.swift

@@ -331,9 +331,21 @@ final class SyncEngine {
 
     func save(workout doc: WorkoutDocument) async {
         guard let store else { return }
+        // The month bucket in a workout's path derives from `start`, so editing the
+        // start date (or a device in a different time zone) can move the file to a new
+        // path. Capture the previously-written path before the upsert overwrites it, so
+        // we can remove the stale file below — otherwise the same id would live at two
+        // paths and the old copy would re-import on the next reconcile.
+        let previousPath = CacheMapper.fetchWorkout(id: doc.id, in: context)?.jsonRelativePath
         do {
             try await store.write(doc, to: doc.relativePath)
             CacheMapper.upsertWorkout(doc, relativePath: doc.relativePath, into: context)
+            // Same id, new path: drop the orphaned file at the old bucket. The id lives
+            // on at the new path, so this is a plain removal — no tombstone (a tombstone
+            // would veto the record that just moved). Phone stays the sole writer.
+            if let previousPath, previousPath != doc.relativePath {
+                try? await store.remove(at: previousPath)
+            }
             saveCacheAndNotify()
             lastSyncError = nil
         } catch {
@@ -619,8 +631,17 @@ final class SyncEngine {
             case .skip:
                 continue
             case .upgrade:
+                // Re-check the veto against fresh state before overwriting — symmetric
+                // with `.write`. The batch above was gathered before a settle-window
+                // race: if the user forked/soft-deleted this seed (clone-on-edit writes
+                // a stub and removes the live file) after we listed the live paths,
+                // rewriting the seed bytes here would transiently resurrect the deleted
+                // seed alongside the user's clone. The stub now present vetoes that.
+                // (No name-collision guard here: on a legitimate upgrade the seed itself
+                // is a live split by that name, so a name check would block every upgrade.)
+                if await tombstones.stubExists(id: seed.id) { continue }
                 // Overwriting an existing seed-path file with canonical bundle bytes is
-                // always safe (the file can only ever be an older seed revision).
+                // otherwise always safe (the file can only ever be an older seed revision).
                 if await writeSeedBytes(seed) { didChange = true }
             case .write:
                 // Re-check the veto and name guards against fresh state — the metadata
@@ -827,7 +848,7 @@ final class SyncEngine {
     /// for the UI to render. Replaces silent `try?` / print-only handling.
     private func report(_ message: String, _ error: Error? = nil) {
         let full = error.map { "\(message): \($0.localizedDescription)" } ?? message
-        print("[Sync] \(full)")
+        log.error("\(full, privacy: .public)")
         lastSyncError = full
     }
 }

Workouts/Views/Settings/SettingsView.swift

@@ -132,7 +132,8 @@ struct SettingsView: View {
                     Text("iCloud Sync")
                 }
 
-                // MARK: - Developer Section
+                // MARK: - Developer Section (debug builds only)
+                #if DEBUG
                 Section {
                     NavigationLink {
                         DuplicateCleanupView()
@@ -142,6 +143,7 @@ struct SettingsView: View {
                 } header: {
                     Text("Developer")
                 }
+                #endif
 
                 // MARK: - About Section
                 Section {