Refactor: RadioButtonGroup focus behavior and orientation-aware navigation

- Radio button indicator no longer pulses, stays static (selected=accent, unselected=border)
- Only focused item shows indicator, not all items
- Vertical orientation: Up/Down arrows navigate, Left/Right ignored
- Horizontal orientation: Left/Right arrows navigate, Up/Down ignored
- Enter/Space always select regardless of orientation
- Pass orientation to RadioButtonGroupHandler for navigation logic
- Updated all handler tests to include orientation parameter
- All 591 tests passing

Sources/TUIkit/Views/RadioButton.swift

@@ -164,6 +164,7 @@ final class RadioButtonGroupHandler: Focusable {
     let focusID: String
     let selection: Binding<AnyHashable>
     let itemValues: [AnyHashable]
+    let orientation: RadioButtonOrientation
     var canBeFocused: Bool
     var focusedIndex: Int = 0
 
@@ -171,11 +172,13 @@ final class RadioButtonGroupHandler: Focusable {
         focusID: String,
         selection: Binding<AnyHashable>,
         itemValues: [AnyHashable],
+        orientation: RadioButtonOrientation,
         canBeFocused: Bool
     ) {
         self.focusID = focusID
         self.selection = selection
         self.itemValues = itemValues
+        self.orientation = orientation
         self.canBeFocused = canBeFocused
 
         // Find current focused index based on selection
@@ -191,6 +194,8 @@ extension RadioButtonGroupHandler {
     func handleKeyEvent(_ event: KeyEvent) -> Bool {
         switch event.key {
         case .up:
+            // Up/Down only work for vertical orientation
+            guard orientation == .vertical else { return false }
             if focusedIndex > 0 {
                 focusedIndex -= 1
                 selection.wrappedValue = itemValues[focusedIndex]
@@ -199,6 +204,8 @@ extension RadioButtonGroupHandler {
             return false
 
         case .down:
+            // Up/Down only work for vertical orientation
+            guard orientation == .vertical else { return false }
             if focusedIndex < itemValues.count - 1 {
                 focusedIndex += 1
                 selection.wrappedValue = itemValues[focusedIndex]
@@ -207,6 +214,8 @@ extension RadioButtonGroupHandler {
             return false
 
         case .left:
+            // Left/Right only work for horizontal orientation
+            guard orientation == .horizontal else { return false }
             if focusedIndex > 0 {
                 focusedIndex -= 1
                 selection.wrappedValue = itemValues[focusedIndex]
@@ -215,6 +224,8 @@ extension RadioButtonGroupHandler {
             return false
 
         case .right:
+            // Left/Right only work for horizontal orientation
+            guard orientation == .horizontal else { return false }
             if focusedIndex < itemValues.count - 1 {
                 focusedIndex += 1
                 selection.wrappedValue = itemValues[focusedIndex]
@@ -256,6 +267,7 @@ extension RadioButtonGroup: Renderable {
             focusID: focusID,
             selection: erasedSelection,
             itemValues: itemValues,
+            orientation: orientation,
             canBeFocused: !isDisabled
         )
         focusManager.register(handler, inSection: context.activeFocusSectionID)
@@ -321,19 +333,19 @@ extension RadioButtonGroup: Renderable {
         // Radio indicator: ● if selected, ◯ if not
         let indicator = isSelected ? "●" : "◯"
 
-        // Determine indicator color
+        // Determine indicator color (static, no pulsing)
         let indicatorColor: Color
         if isDisabled {
             indicatorColor = palette.foregroundTertiary
-        } else if isFocused {
-            // Subtle pulse on focus
-            let dimAccent = palette.accent.opacity(0.35)
-            indicatorColor = Color.lerp(dimAccent, palette.accent, phase: context.pulsePhase)
+        } else if isSelected {
+            // Selected indicator uses accent color
+            indicatorColor = palette.accent
         } else {
+            // Unselected indicator uses border color
             indicatorColor = palette.border
         }
 
-        let styledIndicator = ANSIRenderer.colorize(indicator, foreground: indicatorColor, bold: isFocused && !isDisabled)
+        let styledIndicator = ANSIRenderer.colorize(indicator, foreground: indicatorColor, bold: isSelected && !isDisabled)
 
         // Render label
         let labelView = item.labelBuilder()

Tests/TUIkitTests/RadioButtonTests.swift

@@ -235,7 +235,7 @@ struct RadioButtonGroupTests {
 @Suite("RadioButtonGroupHandler Tests")
 struct RadioButtonGroupHandlerTests {
 
-    @Test("Handler handles arrow down to navigate items")
+    @Test("Handler handles arrow down to navigate items (vertical)")
     func handleArrowDown() {
         var selection = AnyHashable("opt1")
         let binding = Binding(
@@ -248,6 +248,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .vertical,
             canBeFocused: true
         )
 
@@ -259,7 +260,7 @@ struct RadioButtonGroupHandlerTests {
         #expect(selection == AnyHashable("opt2"))
     }
 
-    @Test("Handler handles arrow up to navigate items")
+    @Test("Handler handles arrow up to navigate items (vertical)")
     func handleArrowUp() {
         var selection = AnyHashable("opt2")
         let binding = Binding(
@@ -272,6 +273,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .vertical,
             canBeFocused: true
         )
         handler.focusedIndex = 1
@@ -283,7 +285,7 @@ struct RadioButtonGroupHandlerTests {
         #expect(handler.focusedIndex == 0)
     }
 
-    @Test("Handler handles arrow right (horizontal navigation)")
+    @Test("Handler handles arrow right (horizontal only)")
     func handleArrowRight() {
         var selection = AnyHashable("a")
         let binding = Binding(
@@ -296,6 +298,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .horizontal,
             canBeFocused: true
         )
 
@@ -307,7 +310,7 @@ struct RadioButtonGroupHandlerTests {
         #expect(selection == AnyHashable("b"))
     }
 
-    @Test("Handler handles arrow left (horizontal navigation)")
+    @Test("Handler handles arrow left (horizontal only)")
     func handleArrowLeft() {
         var selection = AnyHashable("b")
         let binding = Binding(
@@ -320,6 +323,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .horizontal,
             canBeFocused: true
         )
         handler.focusedIndex = 1
@@ -345,6 +349,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .vertical,
             canBeFocused: true
         )
         handler.focusedIndex = 1
@@ -369,6 +374,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .vertical,
             canBeFocused: true
         )
         handler.focusedIndex = 1
@@ -393,6 +399,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .vertical,
             canBeFocused: true
         )
 
@@ -417,6 +424,7 @@ struct RadioButtonGroupHandlerTests {
             focusID: "test",
             selection: binding,
             itemValues: itemValues,
+            orientation: .vertical,
             canBeFocused: false
         )