refactor: move V1 code into v1/ subdirectory

- git mv cmd/ internal/ pkg/ test/ go.mod go.sum Makefile build.sh docs/ v1/
- Create v1/README.md with V1 documentation
- Update root README for V1 + V2 structure
- V1 still builds (cd v1 && go build ./cmd/hostkeeper) and 105 tests pass
- Root is now clean for V2 development

v1/pkg/tui/tui_test.go

@@ -0,0 +1,119 @@
+package tui
+
+import (
+	"testing"
+)
+
+func TestTUIInitialization(t *testing.T) {
+	ui := New()
+	if ui == nil {
+		t.Fatal("Failed to initialize TUI")
+	}
+
+	if ui.tabs == nil {
+		t.Fatal("expected tabs manager to be initialized")
+	}
+
+	if ui.tabs.Len() != 1 {
+		t.Errorf("expected 1 tab, got %d", ui.tabs.Len())
+	}
+
+	if ui.Quit {
+		t.Error("expected Quit to be false")
+	}
+
+	// Should have a HostListTab by default
+	ht := FindHostListTab(ui.tabs.tabs)
+	if ht == nil {
+		t.Error("expected HostListTab to be the initial tab")
+	}
+}
+
+func TestTUILoadHosts(t *testing.T) {
+	ui := New()
+	if ui == nil {
+		t.Fatal("Failed to initialize TUI")
+	}
+
+	ui.LoadHosts(nil)
+	if ui.Hosts != nil {
+		t.Error("expected Hosts to be nil")
+	}
+
+	// Should still have a valid tab manager
+	if ui.tabs == nil {
+		t.Fatal("expected tabs manager to be valid")
+	}
+}
+
+func TestTabManagerBasic(t *testing.T) {
+	tm := NewTabManager(NewHostListTab())
+	if tm.Len() != 1 {
+		t.Errorf("expected 1 tab, got %d", tm.Len())
+	}
+
+	if tm.Active() == nil {
+		t.Fatal("expected active tab")
+	}
+
+	if tm.Active().Name() != "Hosts" {
+		t.Errorf("expected 'Hosts', got '%s'", tm.Active().Name())
+	}
+}
+
+func TestTabManagerNavigation(t *testing.T) {
+	tm := NewTabManager(NewHostListTab())
+
+	// Add a second tab
+	second := NewHostListTab()
+	tm.Add(second)
+	if tm.Len() != 2 {
+		t.Errorf("expected 2 tabs, got %d", tm.Len())
+	}
+
+	// Active should now be the last added tab
+	if tm.active != 1 {
+		t.Errorf("expected active index 1, got %d", tm.active)
+	}
+
+	// Previous
+	tm.Prev()
+	if tm.active != 0 {
+		t.Errorf("expected active index 0 after Prev, got %d", tm.active)
+	}
+
+	// Next
+	tm.Next()
+	if tm.active != 1 {
+		t.Errorf("expected active index 1 after Next, got %d", tm.active)
+	}
+}
+
+func TestTabManagerClose(t *testing.T) {
+	tm := NewTabManager(NewHostListTab())
+	second := NewHostListTab()
+	tm.Add(second)
+	tm.Add(NewHostListTab())
+
+	// Close active (last tab)
+	closed := tm.CloseActive()
+	if closed == nil {
+		t.Error("expected closed tab to be returned")
+	}
+
+	if tm.Len() != 2 {
+		t.Errorf("expected 2 tabs after close, got %d", tm.Len())
+	}
+
+	// Close all tabs except last
+	tm.Close(0)
+	if tm.Len() != 1 {
+		t.Errorf("expected 1 tab after close, got %d", tm.Len())
+	}
+
+	// Should not close the last tab via CloseActive (returns nil)
+	result := tm.CloseActive()
+	if result != nil {
+		t.Error("expected nil when trying to close the last tab")
+	}
+}