Add CoreData-based workout tracking app with iOS and watchOS targets

- Migrate from SwiftData to CoreData with CloudKit sync
- Add core models: Split, Exercise, Workout, WorkoutLog
- Implement tab-based UI: Workout Logs, Splits, Settings
- Add SF Symbols picker for split icons
- Add exercise picker filtered by split with exclusion of added exercises
- Integrate IndieAbout for settings/about section
- Add Yams for YAML exercise definition parsing
- Include starter exercise libraries (bodyweight, Planet Fitness)
- Add Date extensions for formatting (formattedTime, isSameDay)
- Format workout date ranges to show time-only for same-day end dates
- Add build number update script
- Add app icons

Workouts/Views/Common/CheckboxStatus.swift

@@ -0,0 +1,48 @@
+//
+// CheckboxStatus.swift
+// Workouts
+//
+// Created by rzen on 7/20/25 at 11:07 AM.
+//
+// Copyright 2025 Rouslan Zenetl. All Rights Reserved.
+//
+
+import SwiftUI
+
+enum CheckboxStatus {
+    case checked
+    case unchecked
+    case intermediate
+    case cancelled
+
+    var color: Color {
+        switch self {
+        case .checked: .green
+        case .unchecked: .gray
+        case .intermediate: .yellow
+        case .cancelled: .red
+        }
+    }
+
+    var systemName: String {
+        switch self {
+        case .checked: "checkmark.circle.fill"
+        case .unchecked: "circle"
+        case .intermediate: "ellipsis.circle"
+        case .cancelled: "xmark.circle"
+        }
+    }
+}
+
+// MARK: - WorkoutStatus Extension
+
+extension WorkoutStatus {
+    var checkboxStatus: CheckboxStatus {
+        switch self {
+        case .notStarted: .unchecked
+        case .inProgress: .intermediate
+        case .completed: .checked
+        case .skipped: .cancelled
+        }
+    }
+}