Add weather feature with WeatherKit integration for mood entries

Fetch and display weather data (temp, condition, hi/lo, humidity) when
users log a mood. Weather is stored as JSON on MoodEntryModel and shown
as a card in EntryDetailView. Premium-gated with location permission
prompt. Includes BGTask retry for failed fetches and full analytics.

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

Shared/Views/NoteEditorView.swift

@@ -187,6 +187,12 @@ struct EntryDetailView: View {
                     // Notes section
                     notesSection
 
+                    // Weather section
+                    if let weatherJSON = entry.weatherJSON,
+                       let weatherData = WeatherData.decode(from: weatherJSON) {
+                        weatherSection(weatherData)
+                    }
+
                     // Photo section
                     photoSection
 
@@ -411,6 +417,16 @@ struct EntryDetailView: View {
         }
     }
 
+    private func weatherSection(_ weatherData: WeatherData) -> some View {
+        VStack(alignment: .leading, spacing: 12) {
+            Text("Weather")
+                .font(.headline)
+                .foregroundColor(textColor)
+
+            WeatherCardView(weatherData: weatherData)
+        }
+    }
+
     private var photoSection: some View {
         VStack(alignment: .leading, spacing: 12) {
             HStack {