Tooltip hint, loading bar, edit shortcut, export/import .lazy

- Keterangan tombol saat hover: baris hint di footer window dan di dalam dialog
  (bukan popup: overlay Fyne menelan klik pertama, tombol jadi perlu 2x klik)
- Dialog proses sekarang pakai progress bar berjalan (bukan spinner diam)
- Tombol edit per shortcut: ganti binary/URL, ikon (file/online), nama, kategori,
  dan lokasi; berkas .desktop + salinan Desktop ditulis ulang, berkas lama dibuang,
  jenis aplikasi dideteksi ulang, binary lama dihapus kalau nama berubah
- Export/Import daftar shortcut ke berkas SQLite .lazy (driver murni Go modernc),
  skema + meta format versi, impor tidak menimpa shortcut yang sudah ada
- Tes: detect kind, edit (rename/ganti binary/ikon/target), db roundtrip, merge impor,
  tooltip (hint muncul/hilang + klik tetap sampai ke tombol), semua paket hijau
- README: bagian backup + hint tombol

internal/db/db.go

@@ -0,0 +1,162 @@
+// Package db menyimpan daftar shortcut LazyRun dalam satu berkas SQLite (.lazy)
+// supaya bisa dipindah antar komputer.
+package db
+
+import (
+	"database/sql"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+	"time"
+
+	_ "modernc.org/sqlite"
+
+	"lazyrun/internal/store"
+)
+
+// FormatVersion dipakai untuk mengenali berkas .lazy buatan LazyRun.
+const FormatVersion = "1"
+
+// DefaultName adalah nama berkas cadangan yang disarankan.
+const DefaultName = "lazyrun-shortcuts.lazy"
+
+const schema = `
+CREATE TABLE meta (
+	key   TEXT PRIMARY KEY,
+	value TEXT NOT NULL
+);
+CREATE TABLE shortcuts (
+	slug              TEXT PRIMARY KEY,
+	name              TEXT NOT NULL,
+	type              TEXT NOT NULL,
+	kind              TEXT,
+	url               TEXT,
+	browser           TEXT,
+	exec_args         TEXT,
+	categories        TEXT,
+	binary_path       TEXT,
+	icon_path         TEXT,
+	icon_source       TEXT,
+	desktop_path      TEXT,
+	desktop_copy_path TEXT,
+	menu              INTEGER NOT NULL,
+	desktop           INTEGER NOT NULL,
+	installed_at      TEXT
+);`
+
+// Export menulis seluruh daftar shortcut ke berkas SQLite baru.
+func Export(path string, appVersion string, items []store.Shortcut) error {
+	if path == "" {
+		return errors.New("lokasi berkas ekspor kosong")
+	}
+	_ = os.Remove(path) // mulai dari berkas baru
+
+	conn, err := sql.Open("sqlite", path)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	if _, err := conn.Exec(schema); err != nil {
+		return err
+	}
+
+	meta := map[string]string{
+		"format":      FormatVersion,
+		"app_version": appVersion,
+		"exported_at": time.Now().UTC().Format(time.RFC3339),
+	}
+	for key, value := range meta {
+		if _, err := conn.Exec("INSERT INTO meta(key, value) VALUES(?, ?)", key, value); err != nil {
+			return err
+		}
+	}
+
+	tx, err := conn.Begin()
+	if err != nil {
+		return err
+	}
+	insert, err := tx.Prepare(`INSERT INTO shortcuts(
+		slug, name, type, kind, url, browser, exec_args, categories,
+		binary_path, icon_path, icon_source, desktop_path, desktop_copy_path,
+		menu, desktop, installed_at) VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)`)
+	if err != nil {
+		tx.Rollback()
+		return err
+	}
+	defer insert.Close()
+
+	for _, item := range items {
+		_, err := insert.Exec(
+			item.Slug, item.Name, item.Type, item.Kind, item.URL, item.Browser,
+			strings.Join(item.ExecArgs, "\x00"), item.Categories,
+			item.BinaryPath, item.IconPath, item.IconSource, item.DesktopPath,
+			item.DesktopCopyPath, boolToInt(item.Targets.Menu), boolToInt(item.Targets.Desktop),
+			item.InstalledAt.Format(time.RFC3339),
+		)
+		if err != nil {
+			tx.Rollback()
+			return err
+		}
+	}
+	return tx.Commit()
+}
+
+// Import membaca daftar shortcut dari berkas .lazy.
+func Import(path string) ([]store.Shortcut, error) {
+	if _, err := os.Stat(path); err != nil {
+		return nil, err
+	}
+
+	conn, err := sql.Open("sqlite", path)
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+
+	var format string
+	if err := conn.QueryRow("SELECT value FROM meta WHERE key = 'format'").Scan(&format); err != nil {
+		return nil, fmt.Errorf("bukan basis data LazyRun: %w", err)
+	}
+	if format != FormatVersion {
+		return nil, fmt.Errorf("versi basis data %s tidak didukung (mendukung %s)", format, FormatVersion)
+	}
+
+	rows, err := conn.Query(`SELECT slug, name, type, kind, url, browser, exec_args,
+		categories, binary_path, icon_path, icon_source, desktop_path,
+		desktop_copy_path, menu, desktop, installed_at FROM shortcuts ORDER BY name`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var items []store.Shortcut
+	for rows.Next() {
+		var item store.Shortcut
+		var args, installed string
+		var menu, desktop int
+		if err := rows.Scan(&item.Slug, &item.Name, &item.Type, &item.Kind, &item.URL,
+			&item.Browser, &args, &item.Categories, &item.BinaryPath, &item.IconPath,
+			&item.IconSource, &item.DesktopPath, &item.DesktopCopyPath,
+			&menu, &desktop, &installed); err != nil {
+			return nil, err
+		}
+		if args != "" {
+			item.ExecArgs = strings.Split(args, "\x00")
+		}
+		item.Targets = store.Targets{Menu: menu != 0, Desktop: desktop != 0}
+		if t, err := time.Parse(time.RFC3339, installed); err == nil {
+			item.InstalledAt = t
+		}
+		items = append(items, item)
+	}
+	return items, rows.Err()
+}
+
+func boolToInt(v bool) int {
+	if v {
+		return 1
+	}
+	return 0
+}