feat: ReactFlux-style confetti — ceiling drop, 200 particles, full screen

Exact replica of ReactFlux confetti:
- 200 tiny rectangles scattered across full screen width
- Drop from above the screen, fall down with gravity
- Gentle horizontal drift + 3D rotation (tumbling effect)
- 10 vivid colors matching ReactFlux palette
- Staggered delays (0-0.4s) for natural rain effect
- 1.5-2.5s fall duration, fade at 80%
- No overlay/checkmark — just pure confetti rain
- Haptic feedback on trigger

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

ios/Platform/Platform/ContentView.swift

@@ -85,178 +85,108 @@ struct MainTabView: View {
     }
 }
 
-// MARK: - Confetti (canvas-confetti style: burst from bottom-right)
+// MARK: - Confetti (ReactFlux style: ceiling drop, full screen scatter)
 
 struct ConfettiView: View {
-    @State private var particles: [Particle] = []
-    @State private var showCheck = false
+    @State private var particles: [ConfettiPiece] = []
 
-    static let palette: [Color] = [
-        .red, .orange, .yellow, .green, .blue, .purple, .pink,
+    static let colors: [Color] = [
+        Color(red: 1, green: 0.22, blue: 0.36),    // hot pink
+        Color(red: 0.26, green: 0.63, blue: 1),     // sky blue
         Color(red: 1, green: 0.84, blue: 0),         // gold
-        Color(red: 0, green: 0.8, blue: 0.6), // teal
-        Color(red: 0.93, green: 0.35, blue: 0.35), // coral
-        Color(red: 0.58, green: 0.44, blue: 0.86), // violet
-        Color(red: 1, green: 0.6, blue: 0.7), // pink
+        Color(red: 0.18, green: 0.8, blue: 0.44),    // green
+        Color(red: 0.61, green: 0.35, blue: 0.96),   // purple
+        Color(red: 1, green: 0.55, blue: 0),          // orange
+        Color(red: 0, green: 0.82, blue: 0.77),       // teal
+        Color(red: 1, green: 0.41, blue: 0.71),       // pink
+        Color(red: 0.39, green: 0.4, blue: 1),        // indigo
+        Color(red: 1, green: 0.92, blue: 0.23),       // yellow
     ]
 
-    struct Particle: Identifiable {
+    struct ConfettiPiece: Identifiable {
         let id = UUID()
         let color: Color
-        let size: CGFloat
-        let shape: Int
-        // Start position (bottom-right area)
-        let startX: CGFloat
+        let width: CGFloat
+        let height: CGFloat
+        let x: CGFloat
         let startY: CGFloat
-        // Velocity
-        let vx: CGFloat
-        let vy: CGFloat
+        let drift: CGFloat
         let spin: Double
         let delay: Double
+        let fallDuration: Double
     }
 
     var body: some View {
         GeometryReader { geo in
             ZStack {
                 ForEach(particles) { p in
-                    particleView(p)
-                        .modifier(PhysicsModifier(
-                            startX: p.startX, startY: p.startY,
-                            vx: p.vx, vy: p.vy,
-                            spin: p.spin, delay: p.delay,
-                            bounds: geo.size
+                    RoundedRectangle(cornerRadius: 1)
+                        .fill(p.color)
+                        .frame(width: p.width, height: p.height)
+                        .modifier(CeilingDropModifier(
+                            x: p.x, startY: p.startY,
+                            endY: geo.size.height + 40,
+                            drift: p.drift, spin: p.spin,
+                            delay: p.delay, duration: p.fallDuration
                         ))
                 }
-
-                // Success check
-                if showCheck {
-                    VStack(spacing: 6) {
-                        Image(systemName: "checkmark.circle.fill")
-                            .font(.system(size: 50))
-                            .foregroundStyle(.white)
-                            .shadow(color: .black.opacity(0.3), radius: 10)
-                        Text("Added!")
-                            .font(.subheadline.weight(.bold))
-                            .foregroundStyle(.white)
-                            .shadow(color: .black.opacity(0.3), radius: 4)
             }
-                    .transition(.scale.combined(with: .opacity))
-                }
-            }
-            .onAppear { generate(size: geo.size) }
+            .onAppear { scatter(in: geo.size) }
         }
     }
 
-    @ViewBuilder
-    private func particleView(_ p: Particle) -> some View {
-        Group {
-            switch p.shape % 3 {
-            case 0: Circle().fill(p.color)
-            case 1: Rectangle().fill(p.color)
-            default: Star(corners: 5, smoothness: 0.45).fill(p.color)
-            }
-        }
-        .frame(width: p.size, height: p.shape % 3 == 1 ? p.size * 0.6 : p.size)
-    }
-
-    private func generate(size: CGSize) {
-        let originX = size.width * 0.9
-        let originY = size.height * 0.85
-
-        // canvas-confetti style: angle=120, spread=70, particleCount=100
-        // angle 120° means shooting upper-left from bottom-right
-        let baseAngle: Double = 120
-        let spread: Double = 70
-
-        particles = (0..<100).map { _ in
-            let angle = baseAngle + Double.random(in: -spread/2...spread/2)
-            let radians = angle * .pi / 180
-            let speed = CGFloat.random(in: 15...45)
-
-            return Particle(
-                color: Self.palette.randomElement()!,
-                size: CGFloat.random(in: 5...11),
-                shape: Int.random(in: 0...2),
-                startX: originX + CGFloat.random(in: -20...20),
-                startY: originY + CGFloat.random(in: -20...20),
-                vx: cos(radians) * speed,
-                vy: -sin(radians) * speed,  // negative = upward
-                spin: Double.random(in: -360...360),
-                delay: Double.random(in: 0...0.15)
+    private func scatter(in size: CGSize) {
+        particles = (0..<200).map { _ in
+            ConfettiPiece(
+                color: Self.colors.randomElement()!,
+                width: CGFloat.random(in: 4...8),
+                height: CGFloat.random(in: 6...14),
+                x: CGFloat.random(in: 0...size.width),
+                startY: CGFloat.random(in: (-200)...(-20)),
+                drift: CGFloat.random(in: -30...30),
+                spin: Double.random(in: -540...540),
+                delay: Double.random(in: 0...0.4),
+                fallDuration: Double.random(in: 1.5...2.5)
             )
         }
-
-        withAnimation(.spring(response: 0.3, dampingFraction: 0.6)) {
-            showCheck = true
-        }
-        DispatchQueue.main.asyncAfter(deadline: .now() + 1.2) {
-            withAnimation(.easeOut(duration: 0.3)) { showCheck = false }
-        }
+        UINotificationFeedbackGenerator().notificationOccurred(.success)
     }
 }
 
-// Physics: gravity pulls down, particles drift and fade
-struct PhysicsModifier: ViewModifier {
-    let startX: CGFloat
+struct CeilingDropModifier: ViewModifier {
+    let x: CGFloat
     let startY: CGFloat
-    let vx: CGFloat
-    let vy: CGFloat
+    let endY: CGFloat
+    let drift: CGFloat
     let spin: Double
     let delay: Double
-    let bounds: CGSize
+    let duration: Double
 
-    @State private var time: CGFloat = 0
+    @State private var progress: CGFloat = 0
     @State private var opacity: Double = 1
 
-    private let gravity: CGFloat = 0.6
-    private let duration: Double = 1.6
-
     func body(content: Content) -> some View {
-        let x = startX + vx * time
-        let y = startY + vy * time + 0.5 * gravity * time * time
-
         content
-            .offset(x: x, y: y)
+            .position(
+                x: x + drift * progress,
+                y: startY + (endY - startY) * progress
+            )
             .opacity(opacity)
-            .rotationEffect(Angle.degrees(spin * Double(time / 30)))
+            .rotation3DEffect(
+                Angle.degrees(spin * Double(progress)),
+                axis: (x: Double.random(in: 0...1), y: Double.random(in: 0...1), z: 0.5)
+            )
             .onAppear {
-                withAnimation(.easeOut(duration: duration).delay(delay)) {
-                    time = 30
+                withAnimation(.easeIn(duration: duration).delay(delay)) {
+                    progress = 1
                 }
-                withAnimation(.easeIn(duration: 0.5).delay(delay + duration * 0.7)) {
+                withAnimation(.easeIn(duration: 0.3).delay(delay + duration * 0.8)) {
                     opacity = 0
                 }
             }
     }
 }
 
-// Star shape
-struct Star: Shape {
-    let corners: Int
-    let smoothness: CGFloat
-
-    func path(in rect: CGRect) -> Path {
-        let center = CGPoint(x: rect.midX, y: rect.midY)
-        let outerRadius = min(rect.width, rect.height) / 2
-        let innerRadius = outerRadius * smoothness
-        var path = Path()
-        let step = .pi / CGFloat(corners)
-
-        for i in 0..<corners * 2 {
-            let angle = CGFloat(i) * step - .pi / 2
-            let radius = i.isMultiple(of: 2) ? outerRadius : innerRadius
-            let point = CGPoint(
-                x: center.x + cos(angle) * radius,
-                y: center.y + sin(angle) * radius
-            )
-            if i == 0 { path.move(to: point) }
-            else { path.addLine(to: point) }
-        }
-        path.closeSubpath()
-        return path
-    }
-}
-
 // MARK: - Assistant Sheet
 
 struct AssistantSheetView: View {