feat(platform): add AURHelper with yay bootstrap and install

internal/platform/aur.go

@@ -0,0 +1,57 @@
+package platform
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// AURHelper abstracts an AUR front-end (currently only yay).
+type AURHelper interface {
+	EnsureInstalled(ctx context.Context) error
+	Install(ctx context.Context, pkgs []string) error
+}
+
+type Yay struct {
+	Runner Runner
+	pm     *Pacman
+}
+
+func NewYay(r Runner) *Yay { return &Yay{Runner: r, pm: NewPacman(r)} }
+
+func (y *Yay) EnsureInstalled(ctx context.Context) error {
+	ok, _ := y.pm.IsInstalled(ctx, "yay")
+	if ok {
+		return nil
+	}
+	// Bootstrap: install build deps, clone AUR yay, makepkg -si.
+	if err := y.pm.Install(ctx, []string{"base-devel", "git"}); err != nil {
+		return err
+	}
+	tmp, err := os.MkdirTemp("", "archduino-yay-")
+	if err != nil {
+		return err
+	}
+	defer os.RemoveAll(tmp)
+	clone := filepath.Join(tmp, "yay")
+	if err := y.Runner.Run(ctx, "git", "clone", "https://aur.archlinux.org/yay.git", clone); err != nil {
+		return err
+	}
+	// `makepkg -si --noconfirm` needs to cd into the cloned dir. os/exec does
+	// not have a per-command cwd without exec.Cmd; our Runner interface does
+	// not expose that, so we invoke via sh -c with a pushd-style prefix.
+	return y.Runner.Run(ctx, "sh", "-c", "cd "+shellQuote(clone)+" && makepkg -si --noconfirm")
+}
+
+func (y *Yay) Install(ctx context.Context, pkgs []string) error {
+	if len(pkgs) == 0 {
+		return nil
+	}
+	args := append([]string{"-S", "--needed", "--noconfirm"}, pkgs...)
+	return y.Runner.Run(ctx, "yay", args...)
+}
+
+func shellQuote(s string) string {
+	return "'" + strings.ReplaceAll(s, "'", `'\''`) + "'"
+}