feat: iOS widgets + fix sleep showing yesterday's data

Widgets:
- HabitsProgressWidget (small/medium): progress ring, completed/total habits, tasks count
- HealthSummaryWidget (small/medium): readiness score, steps, sleep, heart rate
- Shared Keychain access group for app ↔ widget token sharing
- Widget data refreshes every 30 minutes

Sleep fix:
- Changed sleep window from "24 hours back" to "6 PM yesterday → now"
- Captures overnight sleep correctly without showing previous day's data
- Applied to both fetchSleepData (sync) and fetchSleepSegments (detail view)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

PulseHealth/Services/HealthKitService.swift

@@ -154,10 +154,16 @@ class HealthKitService: ObservableObject {
     private func fetchSleepData(dateFormatter: DateFormatter) async -> [[String: Any]] {
         guard let sleepType = HKCategoryType.categoryType(forIdentifier: .sleepAnalysis) else { return [] }
 
-        // Берём последние 24 часа, чтобы захватить ночной сон
+        // Ночной сон: с 18:00 вчера до сейчас (захватывает засыпание вечером + пробуждение утром)
         let now = Date()
-        guard let yesterday = Calendar.current.date(byAdding: .hour, value: -24, to: now) else { return [] }
-        let sleepPredicate = HKQuery.predicateForSamples(withStart: yesterday, end: now)
+        let cal = Calendar.current
+        var startComponents = cal.dateComponents([.year, .month, .day], from: now)
+        startComponents.hour = 18
+        startComponents.minute = 0
+        guard let todayEvening = cal.date(from: startComponents),
+              let yesterdayEvening = cal.date(byAdding: .day, value: -1, to: todayEvening) else { return [] }
+        let sleepStart = now.timeIntervalSince(todayEvening) > 0 ? todayEvening : yesterdayEvening
+        let sleepPredicate = HKQuery.predicateForSamples(withStart: sleepStart, end: now)
 
         return await withCheckedContinuation { cont in
             let sort = NSSortDescriptor(key: HKSampleSortIdentifierStartDate, ascending: true)
@@ -328,8 +334,13 @@ class HealthKitService: ObservableObject {
     func fetchSleepSegments() async -> [SleepSegment] {
         guard let sleepType = HKCategoryType.categoryType(forIdentifier: .sleepAnalysis) else { return [] }
         let now = Date()
-        guard let yesterday = Calendar.current.date(byAdding: .hour, value: -24, to: now) else { return [] }
-        let predicate = HKQuery.predicateForSamples(withStart: yesterday, end: now)
+        let cal = Calendar.current
+        var startComp = cal.dateComponents([.year, .month, .day], from: now)
+        startComp.hour = 18
+        guard let todayEvening = cal.date(from: startComp),
+              let yesterdayEvening = cal.date(byAdding: .day, value: -1, to: todayEvening) else { return [] }
+        let sleepStart = now.timeIntervalSince(todayEvening) > 0 ? todayEvening : yesterdayEvening
+        let predicate = HKQuery.predicateForSamples(withStart: sleepStart, end: now)
 
         return await withCheckedContinuation { cont in
             let sort = NSSortDescriptor(key: HKSampleSortIdentifierStartDate, ascending: true)