feat(tui): add bubbletea terminal UI with entity list, detail, and capture

Adds `nib tui` command and `make tui` target. Scrollable entity list
with j/k navigation, enter for detail view, `a` to capture new entries
using the existing parse grammar, and `d` to delete.

internal/tui/tui.go

@@ -0,0 +1,20 @@
+package tui
+
+import (
+	"fmt"
+	"os"
+
+	tea "github.com/charmbracelet/bubbletea"
+
+	"github.com/lerko/nib/internal/db"
+)
+
+func Run(store *db.Store) error {
+	m := newModel(store)
+	p := tea.NewProgram(m, tea.WithAltScreen(), tea.WithMouseCellMotion())
+	if _, err := p.Run(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		return err
+	}
+	return nil
+}