fix: migrate persisted gamified emojis on load

UserDefaults retained the old 🔥/💥 emojis from before the sample data
was cleaned. On init, replace those emojis in loaded programs and persist
the result so they don't reappear after restart.

KisaniCal/Models/ExerciseModels.swift

@@ -190,7 +190,13 @@ class WorkoutViewModel: ObservableObject {
            let saved = try? JSONDecoder().decode([WorkoutProgram].self, from: data),
            !saved.isEmpty {
 
-            programs = saved
+            let gamifiedEmojis: Set<String> = ["🔥", "💥"]
+            let emojiMap = ["🔥": "🔄", "💥": "🏋️"]
+            let needsMigration = saved.contains(where: { gamifiedEmojis.contains($0.emoji) })
+            programs = needsMigration ? saved.map { p in
+                guard let replacement = emojiMap[p.emoji] else { return p }
+                var copy = p; copy.emoji = replacement; return copy
+            } : saved
 
             var sched: [Int: UUID] = [:]
             if let dict = UserDefaults.standard.dictionary(forKey: Self.kSchedule) as? [String: String] {
@@ -205,7 +211,9 @@ class WorkoutViewModel: ObservableObject {
                let uid = UUID(uuidString: str),
                saved.contains(where: { $0.id == uid }) { pid = uid }
             activeProgramId = pid
-            activeSections  = saved.first { $0.id == pid }?.sections ?? saved[0].sections
+            activeSections  = programs.first { $0.id == pid }?.sections ?? programs[0].sections
+
+            if needsMigration { save() }
 
         } else {
             // ── First launch: seed with sample programs ──