feat(cli): add nib add + nib ls commands

Default command delegation: `nib "..."` routes to `nib add`. Capture
bar parses grammar, creates entities. `nib ls` lists with date
grouping, tag filter, 48h default window. Display glyphs for all
entity types.

cmd/add.go

@@ -0,0 +1,70 @@
+package cmd
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/lerko/nib/internal/db"
+	"github.com/lerko/nib/internal/display"
+	"github.com/lerko/nib/internal/parse"
+	"github.com/spf13/cobra"
+)
+
+var addCmd = &cobra.Command{
+	Use:   "add [input]",
+	Short: "capture a new entity",
+	Args:  cobra.MinimumNArgs(1),
+	RunE:  runAdd,
+}
+
+func runAdd(_ *cobra.Command, args []string) error {
+	input := strings.Join(args, " ")
+
+	parsed, err := parse.Parse(input)
+	if err != nil {
+		return fmt.Errorf("parse: %w", err)
+	}
+
+	store, err := openStore()
+	if err != nil {
+		return err
+	}
+	defer store.Close()
+
+	e := &db.Entity{
+		Body:  parsed.Body,
+		Glyph: db.Glyph(parsed.Glyph),
+		Tags:  parsed.Tags,
+	}
+	if parsed.TimeAnchor != nil {
+		e.TimeAnchor = parsed.TimeAnchor
+	}
+	if parsed.CardSuffix != nil {
+		ct := db.CardType(*parsed.CardSuffix)
+		e.CardType = &ct
+	}
+
+	if err := store.Create(e); err != nil {
+		return err
+	}
+
+	glyph := display.DisplayGlyph(e.Glyph, e.CardType)
+	shortID := display.FormatID(e.ID)
+
+	var parts []string
+	parts = append(parts, glyph)
+	parts = append(parts, " "+e.Body)
+	if e.TimeAnchor != nil {
+		parts = append(parts, " @"+*e.TimeAnchor)
+	}
+	for _, tag := range e.Tags {
+		parts = append(parts, " #"+tag)
+	}
+	parts = append(parts, "  ["+shortID+"]")
+	if e.CardType != nil {
+		parts = append(parts, fmt.Sprintf("  (%s)", *e.CardType))
+	}
+
+	fmt.Println(strings.Join(parts, ""))
+	return nil
+}