feat: calorie tap → fitness, confetti on food add, reduce dashboard padding

- Calorie widget taps switches to Fitness tab
- After adding food: dismiss sheet, switch to Fitness, confetti animation
- Confetti: emoji particles falling + checkmark + haptic feedback
- Dashboard top padding reduced from 60pt to 16pt
- HomeView accepts selectedTab binding

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

ios/Platform/Platform/ContentView.swift

@@ -24,11 +24,12 @@ struct ContentView: View {
 struct MainTabView: View {
     @State private var selectedTab = 0
     @State private var showAssistant = false
+    @State private var showSuccess = false
 
     var body: some View {
-        ZStack(alignment: .bottomTrailing) {
+        ZStack {
             TabView(selection: $selectedTab) {
-                HomeView()
+                HomeView(selectedTab: $selectedTab)
                     .tabItem {
                         Label("Home", systemImage: "house.fill")
                     }
@@ -42,35 +43,146 @@ struct MainTabView: View {
             }
             .tint(Color.accentWarm)
 
-            Button {
-                showAssistant = true
-            } label: {
-                Image(systemName: "plus")
-                    .font(.title2.weight(.semibold))
-                    .foregroundStyle(.white)
-                    .frame(width: 56, height: 56)
-                    .background(Color.accentWarm)
-                    .clipShape(Circle())
-                    .shadow(color: .black.opacity(0.2), radius: 8, y: 4)
+            // Floating + button
+            VStack {
+                Spacer()
+                HStack {
+                    Spacer()
+                    Button {
+                        showAssistant = true
+                    } label: {
+                        Image(systemName: "plus")
+                            .font(.title2.weight(.semibold))
+                            .foregroundStyle(.white)
+                            .frame(width: 56, height: 56)
+                            .background(Color.accentWarm)
+                            .clipShape(Circle())
+                            .shadow(color: .black.opacity(0.2), radius: 8, y: 4)
+                    }
+                    .padding(.trailing, 20)
+                }
+                .padding(.bottom, 70)
+            }
+
+            // Success overlay
+            if showSuccess {
+                SuccessConfettiView()
+                    .ignoresSafeArea()
+                    .allowsHitTesting(false)
             }
-            .padding(.trailing, 20)
-            .padding(.bottom, 70)
         }
         .sheet(isPresented: $showAssistant) {
-            AssistantSheetView()
+            AssistantSheetView(onFoodAdded: {
+                showAssistant = false
+                selectedTab = 1
+                // Show confetti
+                withAnimation { showSuccess = true }
+                DispatchQueue.main.asyncAfter(deadline: .now() + 1.8) {
+                    withAnimation { showSuccess = false }
+                }
+            })
         }
     }
 }
 
+// MARK: - Success Confetti Animation
+
+struct SuccessConfettiView: View {
+    @State private var particles: [ConfettiParticle] = []
+    @State private var checkScale: CGFloat = 0
+
+    struct ConfettiParticle: Identifiable {
+        let id = UUID()
+        let emoji: String
+        let x: CGFloat
+        let delay: Double
+        let duration: Double
+        let rotation: Double
+    }
+
+    var body: some View {
+        ZStack {
+            // Semi-transparent backdrop
+            Color.black.opacity(0.1)
+
+            // Confetti particles
+            ForEach(particles) { p in
+                Text(p.emoji)
+                    .font(.title)
+                    .offset(x: p.x)
+                    .modifier(FallingModifier(delay: p.delay, duration: p.duration, rotation: p.rotation))
+            }
+
+            // Checkmark
+            Image(systemName: "checkmark.circle.fill")
+                .font(.system(size: 60))
+                .foregroundStyle(Color.emerald)
+                .scaleEffect(checkScale)
+                .shadow(color: Color.emerald.opacity(0.3), radius: 20)
+        }
+        .onAppear {
+            // Generate particles
+            let emojis = ["🎉", "✨", "🍎", "🥑", "💚", "⭐️", "🎊"]
+            particles = (0..<15).map { i in
+                ConfettiParticle(
+                    emoji: emojis[i % emojis.length],
+                    x: CGFloat.random(in: -160...160),
+                    delay: Double.random(in: 0...0.3),
+                    duration: Double.random(in: 0.8...1.4),
+                    rotation: Double.random(in: -180...180)
+                )
+            }
+            // Animate checkmark
+            withAnimation(.spring(response: 0.4, dampingFraction: 0.6)) {
+                checkScale = 1.0
+            }
+            // Haptic
+            let generator = UINotificationFeedbackGenerator()
+            generator.notificationOccurred(.success)
+        }
+    }
+}
+
+struct FallingModifier: ViewModifier {
+    let delay: Double
+    let duration: Double
+    let rotation: Double
+
+    @State private var yOffset: CGFloat = -400
+    @State private var opacity: Double = 1
+    @State private var angle: Double = 0
+
+    func body(content: Content) -> some View {
+        content
+            .offset(y: yOffset)
+            .opacity(opacity)
+            .rotationEffect(.degrees(angle))
+            .onAppear {
+                withAnimation(.easeIn(duration: duration).delay(delay)) {
+                    yOffset = 600
+                    opacity = 0
+                    angle = rotation
+                }
+            }
+    }
+}
+
+// Fix: Array doesn't have .length in Swift
+extension Array {
+    var length: Int { count }
+}
+
+// MARK: - Assistant Sheet
+
 struct AssistantSheetView: View {
     @Environment(\.dismiss) private var dismiss
     @State private var selectedMode = 0
+    var onFoodAdded: () -> Void = {}
 
     var body: some View {
         VStack(spacing: 0) {
-            // Custom header — warm background
+            // Custom header
             VStack(spacing: 12) {
-                // Drag handle
                 Capsule()
                     .fill(Color.textTertiary.opacity(0.3))
                     .frame(width: 36, height: 5)
@@ -80,7 +192,6 @@ struct AssistantSheetView: View {
                     .font(.headline)
                     .foregroundStyle(Color.textPrimary)
 
-                // Tab picker — warm styled
                 HStack(spacing: 4) {
                     tabButton("AI Chat", icon: "sparkles", index: 0)
                     tabButton("Quick Add", icon: "magnifyingglass", index: 1)
@@ -93,9 +204,8 @@ struct AssistantSheetView: View {
             .padding(.bottom, 12)
             .background(Color.canvas)
 
-            // Content
             if selectedMode == 0 {
-                AssistantChatView()
+                AssistantChatView(onFoodAdded: onFoodAdded)
             } else {
                 FoodSearchView(isSheet: true)
             }

ios/Platform/Platform/Features/Assistant/AssistantChatView.swift

@@ -3,6 +3,7 @@ import PhotosUI
 
 struct AssistantChatView: View {
     @State private var vm = AssistantViewModel()
+    var onFoodAdded: (() -> Void)?
 
     var body: some View {
         VStack(spacing: 0) {
@@ -113,6 +114,13 @@ struct AssistantChatView: View {
         .onChange(of: vm.selectedPhoto) {
             Task { await vm.handlePhotoSelection() }
         }
+        .onChange(of: vm.applied) {
+            if vm.applied {
+                DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
+                    onFoodAdded?()
+                }
+            }
+        }
     }
 
     // MARK: - Chat Bubble

ios/Platform/Platform/Features/Home/HomeView.swift

@@ -4,8 +4,8 @@ import PhotosUI
 struct HomeView: View {
     @Environment(AuthManager.self) private var auth
     @State private var vm = HomeViewModel()
-    @State private var showAssistant = false
     @State private var ringAnimated = false
+    @Binding var selectedTab: Int
 
     var body: some View {
         ZStack {
@@ -54,12 +54,15 @@ struct HomeView: View {
                         }
                     }
                     .padding(.horizontal)
-                    .padding(.top, 60)
+                    .padding(.top, 16)
 
-                    // Widget grid — half width
+                    // Widget grid — half width, tap to go to fitness
                     HStack(spacing: 12) {
-                        calorieWidget
-                        // Future widget placeholder — invisible spacer
+                        Button { selectedTab = 1 } label: {
+                            calorieWidget
+                        }
+                        .buttonStyle(.plain)
+
                         Color.clear
                     }
                     .padding(.horizontal)