feat(frame): add KeyMap with default bindings

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pkg/cli/frame_model.go

@@ -29,3 +29,30 @@ type modelAdapter struct {
 func (a *modelAdapter) View(w, h int) string                  { return a.m.View(w, h) }
 func (a *modelAdapter) Init() tea.Cmd                         { return nil }
 func (a *modelAdapter) Update(tea.Msg) (FrameModel, tea.Cmd) { return a, nil }
+
+// KeyMap defines key bindings for Frame navigation.
+// Use DefaultKeyMap() for sensible defaults, or build your own.
+type KeyMap struct {
+	FocusNext  tea.KeyType // Tab — cycle focus forward
+	FocusPrev  tea.KeyType // Shift-Tab — cycle focus backward
+	FocusUp    tea.KeyType // Up — spatial: move to Header
+	FocusDown  tea.KeyType // Down — spatial: move to Footer
+	FocusLeft  tea.KeyType // Left — spatial: move to Left sidebar
+	FocusRight tea.KeyType // Right — spatial: move to Right sidebar
+	Back       tea.KeyType // Esc — Navigate back
+	Quit       tea.KeyType // Ctrl-C — quit
+}
+
+// DefaultKeyMap returns the standard Frame key bindings.
+func DefaultKeyMap() KeyMap {
+	return KeyMap{
+		FocusNext:  tea.KeyTab,
+		FocusPrev:  tea.KeyShiftTab,
+		FocusUp:    tea.KeyUp,
+		FocusDown:  tea.KeyDown,
+		FocusLeft:  tea.KeyLeft,
+		FocusRight: tea.KeyRight,
+		Back:       tea.KeyEsc,
+		Quit:       tea.KeyCtrlC,
+	}
+}

pkg/cli/frame_test.go

@@ -247,6 +247,20 @@ func (m *testFrameModel) Update(msg tea.Msg) (FrameModel, tea.Cmd) {
 	return m, nil
 }
 
+func TestKeyMap_Good(t *testing.T) {
+	t.Run("default keymap has expected bindings", func(t *testing.T) {
+		km := DefaultKeyMap()
+		assert.Equal(t, tea.KeyTab, km.FocusNext)
+		assert.Equal(t, tea.KeyShiftTab, km.FocusPrev)
+		assert.Equal(t, tea.KeyUp, km.FocusUp)
+		assert.Equal(t, tea.KeyDown, km.FocusDown)
+		assert.Equal(t, tea.KeyLeft, km.FocusLeft)
+		assert.Equal(t, tea.KeyRight, km.FocusRight)
+		assert.Equal(t, tea.KeyEsc, km.Back)
+		assert.Equal(t, tea.KeyCtrlC, km.Quit)
+	})
+}
+
 // indexOf returns the position of substr in s, or -1 if not found.
 func indexOf(s, substr string) int {
 	for i := range len(s) - len(substr) + 1 {