Fix opaque solid-blue tab bar and MCP sidebar row (glassEffect misuse)

Rune caught this live: the selected MCP tab and "External MCP" sidebar
row rendered as solid opaque blue blocks completely hiding their
icon/label. Root cause: .glassEffect() was nested inside a
.background { } closure applied to a plain Color.clear placeholder,
which isn't how the API is meant to be used — it needs to wrap the real
content directly (as the skill's own examples show), not sit behind it
as an opaque background layer.

Also discovered the skill's documented isEnabled: parameter on
glassEffect(_:in:isEnabled:) isn't available on this SDK build
("extra argument in call") — worked around by branching the view
instead of using that parameter.

Since tabButton/mcpSidebarRow are actual Buttons, switched to the
more correct approach for buttons specifically: native
.buttonStyle(.glass)/.buttonStyle(.glassProminent) for the tab bar
(matching the skill's textbook button pattern) rather than hand-applying
.glassEffect() to custom content. mcpSidebarRow needed to stay on
direct .glassEffect() application (not button styles) since its row
needs to stretch full-width via a trailing Spacer(), which glass
button styles don't support — but applied directly to the real HStack
content this time, branched via if/else, not nested in .background.

Note for the next Rune check: native glass buttons add ~13pt of their
own internal padding, so manual padding was reduced/dropped on
tabButton's label — sizing may look different than before, adjust if
too large/small.

oAI/Views/Screens/SettingsView.swift

@@ -637,21 +637,11 @@ It's better to admit "I need more information" or "I cannot do that" than to fak
     @ViewBuilder
     private func mcpSidebarRow(_ section: MCPSubsection) -> some View {
         Button(action: { selectedMCPSubsection = section }) {
-            HStack(spacing: 10) {
+            Group {
-                Image(systemName: section.icon)
-                    .font(.system(size: 14))
-                    .frame(width: 18)
-                Text(section.label)
-                    .font(.system(size: 13))
-                Spacer()
-            }
-            .padding(.horizontal, 10)
-            .padding(.vertical, 7)
-            .background {
                 if selectedMCPSubsection == section {
-                    Color.clear.glassEffect(.regular.tint(.blue), in: .rect(cornerRadius: 8))
+                    mcpSidebarRowLabel(section).glassEffect(.regular.tint(.blue), in: .rect(cornerRadius: 8))
                 } else {
-                    Color.clear
+                    mcpSidebarRowLabel(section)
                 }
             }
         }
@@ -659,6 +649,20 @@ It's better to admit "I need more information" or "I cannot do that" than to fak
         .foregroundStyle(selectedMCPSubsection == section ? .blue : .primary)
     }
 
+    @ViewBuilder
+    private func mcpSidebarRowLabel(_ section: MCPSubsection) -> some View {
+        HStack(spacing: 10) {
+            Image(systemName: section.icon)
+                .font(.system(size: 14))
+                .frame(width: 18)
+            Text(section.label)
+                .font(.system(size: 13))
+            Spacer()
+        }
+        .padding(.horizontal, 10)
+        .padding(.vertical, 7)
+    }
+
     @ViewBuilder
     private var mcpTabWithSidebar: some View {
         HStack(alignment: .top, spacing: 0) {
@@ -3313,41 +3317,50 @@ It's better to admit "I need more information" or "I cannot do that" than to fak
 
     // MARK: - Tab Navigation
 
+    @ViewBuilder
     private func tabButton(_ tag: Int, icon: String, label: LocalizedStringKey, beta: Bool = false) -> some View {
-        Button(action: { selectedTab = tag }) {
+        let selected = selectedTab == tag
-            VStack(spacing: 3) {
+        Group {
-                ZStack(alignment: .topTrailing) {
+            if selected {
-                    Image(systemName: icon)
+                Button(action: { selectedTab = tag }) {
-                        .font(.system(size: 22))
+                    tabButtonLabel(icon: icon, label: label, beta: beta, selected: true)
-                        .frame(height: 28)
-                        .foregroundStyle(selectedTab == tag ? .blue : .secondary)
-                    if beta {
-                        Text("β")
-                            .font(.system(size: 9, weight: .heavy))
-                            .foregroundStyle(.white)
-                            .padding(.horizontal, 4)
-                            .padding(.vertical, 2)
-                            .background(Color.orange)
-                            .clipShape(Capsule())
-                            .offset(x: 8, y: -3)
-                    }
                 }
-                Text(label)
+                .buttonStyle(.glassProminent)
-                    .font(.system(size: 11))
+                .tint(.blue)
-                    .foregroundStyle(selectedTab == tag ? .blue : .secondary)
+            } else {
-            }
+                Button(action: { selectedTab = tag }) {
-            .frame(minWidth: 55)
+                    tabButtonLabel(icon: icon, label: label, beta: beta, selected: false)
-            .padding(.vertical, 6)
-            .padding(.horizontal, 4)
-            .background {
-                if selectedTab == tag {
-                    Color.clear.glassEffect(.regular.tint(.blue), in: .rect(cornerRadius: 8))
-                } else {
-                    Color.clear
                 }
+                .buttonStyle(.glass)
             }
         }
-        .buttonStyle(.plain)
+        .buttonBorderShape(.roundedRectangle(radius: 8))
+    }
+
+    @ViewBuilder
+    private func tabButtonLabel(icon: String, label: LocalizedStringKey, beta: Bool, selected: Bool) -> some View {
+        VStack(spacing: 3) {
+            ZStack(alignment: .topTrailing) {
+                Image(systemName: icon)
+                    .font(.system(size: 22))
+                    .frame(height: 28)
+                    .foregroundStyle(selected ? .blue : .secondary)
+                if beta {
+                    Text("β")
+                        .font(.system(size: 9, weight: .heavy))
+                        .foregroundStyle(.white)
+                        .padding(.horizontal, 4)
+                        .padding(.vertical, 2)
+                        .background(Color.orange)
+                        .clipShape(Capsule())
+                        .offset(x: 8, y: -3)
+                }
+            }
+            Text(label)
+                .font(.system(size: 11))
+                .foregroundStyle(selected ? .blue : .secondary)
+        }
+        .frame(minWidth: 55)
     }
 
     private func tabTitle(_ tag: Int) -> LocalizedStringKey {