feat(cli): add archive command for cross-host data transport (#610)

* feat(cli): add archive command for cross-host data transport
* fix(archive): correct flat-layout path and entry-count wording
* refactor(archive): rename BuildArchive to WriteArchive

browser/archive.go

@@ -0,0 +1,68 @@
+package browser
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/moond4rk/hackbrowserdata/browser/chromium"
+	"github.com/moond4rk/hackbrowserdata/filemanager"
+	"github.com/moond4rk/hackbrowserdata/log"
+	"github.com/moond4rk/hackbrowserdata/types"
+	"github.com/moond4rk/hackbrowserdata/utils/fileutil"
+)
+
+// Archivable is implemented by installations that can enumerate their decryption-relevant files for
+// cross-host transport (Chromium only).
+type Archivable interface {
+	BrowserKey() string
+	ArchiveSources(categories []types.Category) []chromium.ArchiveSource
+}
+
+// WriteArchive packs each browser's decryption-relevant files into a zip whose internal layout is
+// <browser-key>/<User Data layout>, so a restore can re-expand it and decrypt with a keys.json. Files
+// are staged through a locked-file session first because Windows holds exclusive SQLite locks. Returns
+// the number of source entries staged (a directory source counts once).
+func WriteArchive(browsers []Browser, categories []types.Category, outPath string) (int, error) {
+	session, err := filemanager.NewSession()
+	if err != nil {
+		return 0, err
+	}
+	defer session.Cleanup()
+
+	staging := session.TempDir()
+	seen := make(map[string]bool)
+	count := 0
+	for _, b := range browsers {
+		archivable, ok := b.(Archivable)
+		if !ok {
+			continue
+		}
+		key := archivable.BrowserKey()
+		for _, src := range archivable.ArchiveSources(categories) {
+			entry := key + "/" + src.LayoutRel
+			if seen[entry] {
+				continue
+			}
+			seen[entry] = true
+
+			dst := filepath.Join(staging, key, filepath.FromSlash(src.LayoutRel))
+			if err := os.MkdirAll(filepath.Dir(dst), 0o755); err != nil {
+				log.Warnf("archive: %s: %v", entry, err)
+				continue
+			}
+			if err := session.Acquire(src.AbsPath, dst, src.IsDir); err != nil {
+				log.Warnf("archive: acquire %s: %v", entry, err)
+				continue
+			}
+			count++
+		}
+	}
+	if count == 0 {
+		return 0, fmt.Errorf("no decryption-relevant files found to archive")
+	}
+	if err := fileutil.ZipDir(outPath, staging); err != nil {
+		return 0, fmt.Errorf("write archive %s: %w", outPath, err)
+	}
+	return count, nil
+}