Restructure into a three-tab app with Progress, goals, and Meditation

The UX redesign's first landing (spec in UX-REDESIGN.md): ContentView
becomes a Today / Progress / Settings TabView, "Routine" replaces
"Split" in every user-facing string and view name (code-level types
keep their names), and workout starting moves to shared
WorkoutStarter / StartedWorkoutNavigator plumbing.

- New Progress tab: weekly goal streaks, workout trends, per-exercise
  weight progression, achievements, and the full history list
  (WorkoutLogsView -> WorkoutHistoryView).
- Goals: stable categories workouts roll up to, managed from Settings.
- New Meditation exercise + starter routine; timed sits record to
  Apple Health as Mind & Body sessions.

Claude-Session: https://claude.ai/code/session_012qw2itfzKyEJ1HpsFt8Ex4

Workouts/Views/Exercises/ExerciseListView.swift

@@ -15,41 +15,41 @@ struct ExerciseListView: View {
     @Environment(SyncEngine.self) private var sync
     @Environment(\.dismiss) private var dismiss
 
-    // Resolve the split by id, not a captured entity: editing a seed's exercise from
+    // Resolve the routine by id, not a captured entity: editing a seed's exercise from
     // here clones the seed (new identity, old entity deleted), which would dangle a
-    // stored `Split`. `currentSplitID` follows that swap.
-    @State private var splitID: String
-    @Query private var splits: [Split]
+    // stored `Routine`. `currentRoutineID` follows that swap.
+    @State private var routineID: String
+    @Query private var routines: [Routine]
 
     @State private var showingAddSheet: Bool = false
     @State private var itemToEdit: Exercise? = nil
     @State private var itemToDelete: Exercise? = nil
     @AppStorage("weightUnit") private var weightUnit: WeightUnit = .lb
 
-    init(split: Split) {
-        _splitID = State(initialValue: split.id)
+    init(routine: Routine) {
+        _routineID = State(initialValue: routine.id)
     }
 
-    private var split: Split? {
-        let id = sync.currentSplitID(for: splitID)
-        return splits.first { $0.id == id }
+    private var routine: Routine? {
+        let id = sync.currentRoutineID(for: routineID)
+        return routines.first { $0.id == id }
     }
 
     var body: some View {
         Group {
-            if let split {
-                content(for: split)
+            if let routine {
+                content(for: routine)
             } else {
-                ContentUnavailableView("Split Unavailable", systemImage: "dumbbell")
+                ContentUnavailableView("Routine Unavailable", systemImage: "dumbbell")
                     .task { dismiss() }
             }
         }
     }
 
     @ViewBuilder
-    private func content(for split: Split) -> some View {
+    private func content(for routine: Routine) -> some View {
         Form {
-            let sortedExercises = split.exercisesArray
+            let sortedExercises = routine.exercisesArray
 
             if !sortedExercises.isEmpty {
                 ForEach(sortedExercises) { item in
@@ -86,14 +86,14 @@ struct ExerciseListView: View {
                 }
             }
         }
-        .navigationTitle(split.name)
+        .navigationTitle(routine.name)
         .sheet(isPresented: $showingAddSheet) {
             ExercisePickerView(onExerciseSelected: { exerciseNames in
                 addExercises(names: exerciseNames)
             }, allowMultiSelect: true)
         }
         .sheet(item: $itemToEdit) { item in
-            ExerciseAddEditView(exercise: item, split: split)
+            ExerciseAddEditView(exercise: item, routine: routine)
         }
         .confirmationDialog(
             "Delete Exercise?",
@@ -112,29 +112,29 @@ struct ExerciseListView: View {
                 itemToDelete = nil
             }
         } message: { item in
-            Text("Remove \"\(item.name)\" from this split?")
+            Text("Remove \"\(item.name)\" from this routine?")
         }
     }
 
     // MARK: - Helpers
 
     private func moveExercises(from source: IndexSet, to destination: Int) {
-        guard let split else { return }
-        var exercises = split.exercisesArray
+        guard let routine else { return }
+        var exercises = routine.exercisesArray
         exercises.move(fromOffsets: source, toOffset: destination)
-        var doc = SplitDocument(from: split)
+        var doc = RoutineDocument(from: routine)
         doc.exercises = exercises.enumerated().map { i, ex in
             var ed = ExerciseDocument(from: ex)
             ed.order = i
             return ed
         }
         doc.updatedAt = Date()
-        Task { await sync.save(split: doc) }
+        Task { await sync.save(routine: doc) }
     }
 
     private func addExercises(names: [String]) {
-        guard let split else { return }
-        var doc = SplitDocument(from: split)
+        guard let routine else { return }
+        var doc = RoutineDocument(from: routine)
         let existingNames = Set(doc.exercises.map { $0.name })
         let base = doc.exercises.count
         let newDocs = names
@@ -154,17 +154,17 @@ struct ExerciseListView: View {
             }
         doc.exercises.append(contentsOf: newDocs)
         doc.updatedAt = Date()
-        Task { await sync.save(split: doc) }
+        Task { await sync.save(routine: doc) }
     }
 
     private func deleteExercise(_ exercise: Exercise) {
-        guard let split else { return }
-        var doc = SplitDocument(from: split)
+        guard let routine else { return }
+        var doc = RoutineDocument(from: routine)
         doc.exercises.removeAll { $0.id == exercise.id }
         for i in doc.exercises.indices {
             doc.exercises[i].order = i
         }
         doc.updatedAt = Date()
-        Task { await sync.save(split: doc) }
+        Task { await sync.save(routine: doc) }
     }
 }