refactor(cli): flatten keys export/import into dumpkeys/restore (#608)

* refactor(cli): flatten keys export/import into dumpkeys/restore

The keys noun-group clashed with the flat dump/list verbs; unify on flat verbs and drop the keys parent. Pure rename, no behavior change.

* docs(rfc): add RFC-013 CLI redesign & cross-host restore

The accepted design doc for the flat-verb CLI redesign and cross-platform restore.

cmd/hack-browser-data/dumpkeys.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"github.com/moond4rk/hackbrowserdata/browser"
+	"github.com/moond4rk/hackbrowserdata/log"
+)
+
+func dumpKeysCmd() *cobra.Command {
+	var (
+		browserName string
+		outputPath  string
+		keychainPw  string
+	)
+
+	cmd := &cobra.Command{
+		Use:   "dumpkeys",
+		Short: "Export Chromium master keys as JSON for cross-host decryption",
+		Example: `  hack-browser-data dumpkeys -o keys.json
+  hack-browser-data dumpkeys -b chrome`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			browsers, err := browser.DiscoverBrowsersWithKeys(browser.DiscoverOptions{
+				Name:             browserName,
+				KeychainPassword: keychainPw,
+			})
+			if err != nil {
+				return err
+			}
+
+			dump := browser.BuildDump(browsers)
+			log.Infof("Exported keys for %d vault(s)", len(dump.Vaults))
+
+			if outputPath == "" {
+				return dump.WriteJSON(os.Stdout)
+			}
+			f, err := os.OpenFile(outputPath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0o600)
+			if err != nil {
+				return fmt.Errorf("create %s: %w", outputPath, err)
+			}
+			defer f.Close()
+			return dump.WriteJSON(f)
+		},
+	}
+
+	cmd.Flags().StringVarP(&browserName, "browser", "b", "all", "target browser: all|"+browser.Names())
+	cmd.Flags().StringVarP(&outputPath, "output", "o", "", "output file (default: stdout)")
+	cmd.Flags().StringVar(&keychainPw, "keychain-pw", "", "macOS keychain password")
+
+	return cmd
+}