Fix 8 audit items: remove force-unwraps, improve accessibility and concurrency

- Replace force-unwrap HK types with modern HKQuantityType(_:) initializer
- Replace Calendar.date force-unwraps with guard/let in HealthService, HeaderPercView, MoodStreakActivity, DayViewViewModel, MonthTotalTemplate
- Extract DayViewViewModel.countEntries into testable static method with safe flatMap
- Replace DispatchQueue.main.asyncAfter with Task.sleep in CelebrationAnimations
- Add .minimumScaleFactor(0.5) to SmallRollUpHeaderView for Dynamic Type
- Add VoiceOver accessibility labels to HeaderPercView mood percentages
- Fix @testable import iFeel → Feels in Tests_iOS.swift
- Add 4 unit tests for countEntries (TDD)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

FeelsTests/DayViewViewModelTests.swift

@@ -0,0 +1,42 @@
+//
+//  DayViewViewModelTests.swift
+//  FeelsTests
+//
+//  Unit tests for DayViewViewModel.countEntries — verifies safe counting
+//  across various grouped dictionary shapes (TDD for force-unwrap fix).
+//
+
+import XCTest
+import SwiftData
+@testable import Feels
+
+@MainActor
+final class DayViewViewModelTests: XCTestCase {
+
+    func testCountEntries_EmptyGrouped() {
+        let grouped: [Int: [Int: [MoodEntryModel]]] = [:]
+        XCTAssertEqual(DayViewViewModel.countEntries(in: grouped), 0)
+    }
+
+    func testCountEntries_SingleYearSingleMonth() {
+        let entry = MoodEntryModel(forDate: Date(), mood: .great, entryType: .listView)
+        let grouped: [Int: [Int: [MoodEntryModel]]] = [2026: [2: [entry]]]
+        XCTAssertEqual(DayViewViewModel.countEntries(in: grouped), 1)
+    }
+
+    func testCountEntries_MultipleYearsAndMonths() {
+        let e1 = MoodEntryModel(forDate: Date(), mood: .great, entryType: .listView)
+        let e2 = MoodEntryModel(forDate: Date(), mood: .good, entryType: .listView)
+        let e3 = MoodEntryModel(forDate: Date(), mood: .bad, entryType: .listView)
+        let grouped: [Int: [Int: [MoodEntryModel]]] = [
+            2025: [12: [e1, e2]],
+            2026: [1: [e3], 2: [e1, e2, e3]]
+        ]
+        XCTAssertEqual(DayViewViewModel.countEntries(in: grouped), 6)
+    }
+
+    func testCountEntries_YearWithEmptyMonth() {
+        let grouped: [Int: [Int: [MoodEntryModel]]] = [2026: [1: []]]
+        XCTAssertEqual(DayViewViewModel.countEntries(in: grouped), 0)
+    }
+}