wip: Nearlight redesign implementation

Sources/Features/Conversation/LightwellView.swift

@@ -0,0 +1,122 @@
+import SwiftUI
+import UIKit
+
+/// The Nearlight signature element: an upright, softly lit aperture.
+///
+/// Two capsules in a ZStack — no assets, shaders, blur, or particles. The
+/// inner capsule carries a vertical Rosewood gradient; its geometry encodes
+/// conversation state and audio level. Noninteractive and accessibility
+/// hidden: the companion status text carries meaning.
+struct LightwellView: View {
+    /// Lightwell presentation state, mapped from session/conversation models.
+    enum Phase: Equatable {
+        case idle
+        case connecting
+        case waiting
+        case listening(level: Double)
+        case thinking
+        case speaking(level: Double)
+        case tearingDown
+        case failed
+        /// Input never drives the light (muted or Type mode).
+        case readyNoInput
+    }
+
+    let phase: Phase
+    /// Compact (24×36) in the conversation status strip; full (64×96) on welcome.
+    var compact: Bool = false
+    @Environment(\.accessibilityReduceMotion) private var reduceMotion
+    /// Pending-state pulse driver, 0 → 1 → 0 over the 2.4s cycle.
+    @State private var pulse: Double = 0
+
+    /// Frame dimensions never animate; inner dimensions multiply by 0.375
+    /// in the compact frame.
+    private var frameSize: CGSize {
+        compact ? CGSize(width: 24, height: 36) : CGSize(width: 64, height: 96)
+    }
+    private var baseInner: CGSize {
+        let base = CGSize(width: 16, height: 40)
+        return compact
+            ? CGSize(width: base.width * 0.375, height: base.height * 0.375)
+            : base
+    }
+
+    var body: some View {
+        let inner = innerSize
+        ZStack {
+            Capsule()
+                .fill(Nearlight.surface)
+            Capsule()
+                .fill(
+                    LinearGradient(
+                        stops: [
+                            .init(color: Nearlight.rosewood.opacity(0.35), location: 0),
+                            .init(color: Nearlight.rosewood.opacity(1), location: 0.5),
+                            .init(color: Nearlight.rosewood.opacity(0.55), location: 1),
+                        ],
+                        startPoint: .top, endPoint: .bottom
+                    )
+                )
+                .frame(width: inner.width, height: inner.height)
+                .opacity(overallOpacity)
+                .animation(reduceMotion ? nil : Nearlight.quick, value: overallOpacity)
+                .animation(reduceMotion ? nil : Nearlight.settle, value: innerSize)
+        }
+        .frame(width: frameSize.width, height: frameSize.height)
+        .overlay(
+            Capsule().strokeBorder(Nearlight.quiet, lineWidth: 1)
+        )
+        .accessibilityHidden(true)
+        .task(id: pulseActive) {
+            guard pulseActive else {
+                pulse = 0
+                return
+            }
+            while !Task.isCancelled {
+                withAnimation(reduceMotion ? nil : Nearlight.cycle) { pulse = pulse == 0 ? 1 : 0 }
+                try? await Task.sleep(for: .seconds(2.4))
+            }
+        }
+    }
+
+    /// Whether the pulse loop should run for this phase.
+    private var pulseActive: Bool {
+        switch phase {
+        case .connecting, .waiting, .thinking: return !reduceMotion
+        default: return false
+        }
+    }
+
+    /// Inner capsule geometry per spec table. `a` is the smoothed level.
+    private var innerSize: CGSize {
+        let base = baseInner
+        switch phase {
+        case .listening(let a):
+            let level = min(max(a, 0), 1)
+            return CGSize(width: base.width + (compact ? 3 : 8) * level,
+                          height: base.height + (compact ? 6 : 16) * level)
+        case .speaking(let a):
+            let level = min(max(a, 0), 1)
+            return CGSize(width: base.width + (compact ? 4.5 : 12) * level,
+                          height: base.height + (compact ? 9 : 24) * level)
+        case .waiting, .thinking:
+            // Pulse drives opacity; height steps up one band.
+            return CGSize(width: base.width, height: base.height + (compact ? 3 : 8))
+        case .connecting, .idle, .failed, .tearingDown, .readyNoInput:
+            return base
+        }
+    }
+
+    private var overallOpacity: Double {
+        switch phase {
+        case .connecting, .waiting:
+            return 0.45 + 0.45 * pulse
+        case .thinking:
+            return 0.65 + 0.35 * pulse
+        case .idle, .failed, .tearingDown:
+            return 0.45
+        case .listening, .speaking, .readyNoInput:
+            return 1
+        }
+    }
+}