Remove #if DEBUG guards for TestFlight, polish weekly digest and insights UX

- Remove #if DEBUG from all debug settings, exporters, and IAP bypass so
  debug options are available in TestFlight builds
- Weekly digest card: replace dismiss X with collapsible chevron caret
- Weekly digest: generate on-demand when opening Insights tab if no cached
  digest exists (BGTask + notification kept as bonus path)
- Fix digest intention text color (was .secondary, now uses theme textColor)
- Add "Generate Weekly Digest" debug button in Settings
- Add generating overlay on Insights tab with pulsing sparkles icon that
  stays visible until all sections finish loading (content at 0.2 opacity)

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

Shared/Persisence/DataControllerHelper.swift

@@ -26,7 +26,6 @@ extension DataController {
     }
 
     func populateMemory() {
-        #if DEBUG
         for idx in 1..<255 {
             let date = Calendar.current.date(byAdding: .day, value: -idx, to: Date())!
             var moodValue = Int.random(in: 2...4)
@@ -43,7 +42,6 @@ extension DataController {
             modelContext.insert(entry)
         }
         save()
-        #endif
     }
 
     /// Creates an entry that is NOT inserted into the context - used for UI placeholders
@@ -79,7 +77,6 @@ extension DataController {
         saveAndRunDataListeners()
     }
 
-    #if DEBUG
     func populate2YearsData() {
         clearDB()
 
@@ -100,7 +97,6 @@ extension DataController {
 
         saveAndRunDataListeners()
     }
-    #endif
 
     private static func randomMood() -> Mood {
         var moodValue = Int.random(in: 3...4)