feat: tip IAP, commercial GitHub Pages, and App Store screenshots

Add optional StoreKit support tip (features stay free), redesign the
landing page with zh/en + light/dark and product shots, and ship
iPhone/iPad/Mac App Store screenshot sets.

OSGKeyboardMac/DashboardView.swift

@@ -38,8 +38,9 @@ struct DashboardView: View {
                     .padding(.top, Spacing.sm)
 
                     // Leftover window height splits evenly above / below the mic
-                    // bar so spacing stays balanced at any window size.
-                    Spacer(minLength: Spacing.xs)
+                    // bar so spacing stays balanced at any window size. The top
+                    // gap keeps a larger floor so the mic never hugs the canvas.
+                    Spacer(minLength: 30)
 
                     BottomDictationBar(viewModel: viewModel)
                         .padding(.horizontal, MacMetrics.pageHorizontalInset)

OSGKeyboardMac/MacOnboardingView.swift

@@ -261,13 +261,20 @@ struct MacOnboardingView: View {
     @ViewBuilder
     private var heroIcon: some View {
         if model.step == .welcome {
-            Image("OSGBrandMark")
-                .renderingMode(.template)
-                .resizable()
-                .scaledToFit()
-                .frame(width: 128, height: 128)
-                .foregroundStyle(colorScheme == .dark ? Color.white : palette.accent)
-                .accessibilityLabel("OSGKeyboard")
+            ZStack {
+                SonicParticleField()
+                    .frame(width: 300, height: 300)
+
+                Image("OSGBrandMark")
+                    .renderingMode(.template)
+                    .resizable()
+                    .scaledToFit()
+                    .frame(width: 128, height: 128)
+                    .foregroundStyle(colorScheme == .dark ? Color.white : palette.accent)
+                    .accessibilityLabel("OSGKeyboard")
+                    .allowsHitTesting(false)
+            }
+            .frame(width: 300, height: 300)
         } else {
             ZStack {
                 Circle()

OSGKeyboardMac/MacSettingsView.swift

@@ -39,6 +39,7 @@ struct MacSettingsView: View {
 
                 ScrollView {
                     LazyVStack(alignment: .leading, spacing: Spacing.xl) {
+                        supportSection
                         generalSection
                         recognitionSection
                         if viewModel.config.engineMode == "cloud" {
@@ -298,6 +299,17 @@ struct MacSettingsView: View {
         }
     }
 
+    // MARK: - Support developer
+
+    private var supportSection: some View {
+        MacSettingsSection(
+            title: MacL10n.string("tip.title", language: lang),
+            footer: MacL10n.string("tip.consumableNotice", language: lang)
+        ) {
+            MacSupportDeveloperTipRows(language: lang)
+        }
+    }
+
     // MARK: - Legal
 
     private var legalSection: some View {

OSGKeyboardMac/MacSupportDeveloperTipRows.swift

@@ -0,0 +1,89 @@
+// MacSupportDeveloperTipRows.swift
+// OSGKeyboard · Mac
+//
+// Optional consumable tip rows for macOS Settings.
+
+import SwiftUI
+
+struct MacSupportDeveloperTipRows: View {
+    @ObservedObject private var tipManager = TipPurchaseManager.shared
+    @Environment(\.themePalette) private var palette
+
+    let language: AppUILanguage
+
+    @State private var showThankYouAlert = false
+    @State private var showErrorAlert = false
+    @State private var errorMessage = ""
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: MacMetrics.settingsRowGap) {
+            SupportDeveloperTipBody(language: language)
+                .padding(.horizontal, MacMetrics.settingsCardInset)
+
+            if tipManager.supportCount > 0 {
+                Text(
+                    SharedL10n.format(
+                        "tip.thankYou.past",
+                        language: language,
+                        tipManager.supportCount
+                    )
+                )
+                .font(TypeStyle.caption)
+                .foregroundStyle(palette.accent)
+                .padding(.horizontal, MacMetrics.settingsCardInset)
+            }
+
+            MacSettingsToolButton(title: tipButtonTitle, disabled: isPurchaseInFlight) {
+                Task { await tipManager.purchase() }
+            }
+            .padding(.horizontal, MacMetrics.settingsCardInset)
+        }
+        .onChange(of: tipManager.purchaseState) { _, newValue in
+            switch newValue {
+            case .succeeded:
+                showThankYouAlert = true
+            case .failed(let message):
+                errorMessage = message
+                showErrorAlert = true
+            default:
+                break
+            }
+        }
+        .alert(
+            SharedL10n.string("tip.thankYou.title", language: language),
+            isPresented: $showThankYouAlert
+        ) {
+            Button(SharedL10n.string("tip.alert.dismiss", language: language)) {
+                tipManager.acknowledgePurchaseState()
+            }
+        } message: {
+            Text(SharedL10n.string("tip.thankYou.message", language: language))
+        }
+        .alert(
+            SharedL10n.string("tip.error.title", language: language),
+            isPresented: $showErrorAlert
+        ) {
+            Button(SharedL10n.string("tip.alert.dismiss", language: language)) {
+                tipManager.acknowledgePurchaseState()
+            }
+        } message: {
+            Text(errorMessage)
+        }
+    }
+
+    private var isPurchaseInFlight: Bool {
+        switch tipManager.purchaseState {
+        case .loading, .purchasing:
+            return true
+        default:
+            return false
+        }
+    }
+
+    private var tipButtonTitle: String {
+        if let product = tipManager.product {
+            return SharedL10n.format("tip.button", language: language, product.displayPrice)
+        }
+        return SharedL10n.string("tip.buttonFallback", language: language)
+    }
+}