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/Settings/DuplicateCleanupView.swift

@@ -7,10 +7,10 @@
 
 import SwiftUI
 
-/// Developer-facing tool: scans iCloud Drive for splits/workouts that are exact
+/// Developer-facing tool: scans iCloud Drive for routines/workouts that are exact
 /// content duplicates (see `DuplicateCleanupPlanner`) — typically the residue of
 /// testing, a restore, or a sync hiccup — and offers to delete the extras. Never
-/// touches a split referenced by a workout, a bundled starter split, or an
+/// touches a routine referenced by a workout, a bundled starter routine, or an
 /// in-progress workout.
 struct DuplicateCleanupView: View {
     @Environment(SyncEngine.self) private var sync
@@ -21,7 +21,7 @@ struct DuplicateCleanupView: View {
     }
 
     private struct CleanupSummary {
-        var splitsDeleted: Int
+        var routinesDeleted: Int
         var workoutsDeleted: Int
         var skipped: Int
     }
@@ -58,7 +58,7 @@ struct DuplicateCleanupView: View {
                     pendingPlan = nil
                 }
             } message: { _ in
-                Text("This permanently deletes the duplicate copies shown below. Referenced splits, starter splits, and in-progress workouts are always kept.")
+                Text("This permanently deletes the duplicate copies shown below. Referenced routines, starter routines, and in-progress workouts are always kept.")
             }
     }
 
@@ -93,7 +93,7 @@ struct DuplicateCleanupView: View {
                     Label("Scan for Duplicates", systemImage: "magnifyingglass")
                 }
             } footer: {
-                Text("Looks for splits and workouts that are exact content duplicates — for example, left over from testing or a sync hiccup — and offers to delete the extra copies. Splits referenced by a workout, starter splits, and in-progress workouts are never deleted.")
+                Text("Looks for routines and workouts that are exact content duplicates — for example, left over from testing or a sync hiccup — and offers to delete the extra copies. Routines referenced by a workout, starter routines, and in-progress workouts are never deleted.")
             }
         }
     }
@@ -110,10 +110,10 @@ struct DuplicateCleanupView: View {
             )
         } else {
             List {
-                if !plan.splitGroups.isEmpty {
-                    Section("Duplicate Splits") {
-                        ForEach(plan.splitGroups) { group in
-                            splitGroupRow(group)
+                if !plan.routineGroups.isEmpty {
+                    Section("Duplicate Routines") {
+                        ForEach(plan.routineGroups) { group in
+                            routineGroupRow(group)
                         }
                     }
                 }
@@ -139,7 +139,7 @@ struct DuplicateCleanupView: View {
         }
     }
 
-    private func splitGroupRow(_ group: DuplicateCleanupPlan.SplitGroup) -> some View {
+    private func routineGroupRow(_ group: DuplicateCleanupPlan.RoutineGroup) -> some View {
         VStack(alignment: .leading, spacing: 6) {
             ForEach(group.keep) { doc in
                 memberRow(name: doc.name, detail: "\(doc.exercises.count) exercises", id: doc.id, isKeep: true)
@@ -154,14 +154,14 @@ struct DuplicateCleanupView: View {
     private func workoutGroupRow(_ group: DuplicateCleanupPlan.WorkoutGroup) -> some View {
         VStack(alignment: .leading, spacing: 6) {
             memberRow(
-                name: group.keep.splitName ?? "(no split)",
+                name: group.keep.routineName ?? "(no routine)",
                 detail: group.keep.start.formattedDate(),
                 id: group.keep.id,
                 isKeep: true
             )
             ForEach(group.delete) { doc in
                 memberRow(
-                    name: doc.splitName ?? "(no split)",
+                    name: doc.routineName ?? "(no routine)",
                     detail: doc.start.formattedDate(),
                     id: doc.id,
                     isKeep: false
@@ -237,7 +237,7 @@ struct DuplicateCleanupView: View {
         List {
             Section {
                 Label(
-                    "Deleted \(summary.splitsDeleted) split\(summary.splitsDeleted == 1 ? "" : "s"), \(summary.workoutsDeleted) workout\(summary.workoutsDeleted == 1 ? "" : "s"). \(summary.skipped) skipped (referenced or active).",
+                    "Deleted \(summary.routinesDeleted) routine\(summary.routinesDeleted == 1 ? "" : "s"), \(summary.workoutsDeleted) workout\(summary.workoutsDeleted == 1 ? "" : "s"). \(summary.skipped) skipped (referenced or active).",
                     systemImage: "checkmark.circle.fill"
                 )
                 .foregroundStyle(.green)
@@ -273,7 +273,7 @@ struct DuplicateCleanupView: View {
         phase = .deleting
         let result = await sync.performCleanup(plan)
         phase = .done(CleanupSummary(
-            splitsDeleted: result.splitsDeleted,
+            routinesDeleted: result.routinesDeleted,
             workoutsDeleted: result.workoutsDeleted,
             skipped: result.skipped
         ))