build: add reproducible release bundles

cmd/rvc/main.go

@@ -25,6 +25,9 @@ import (
 
 const defaultControlSocket = "/run/rvbox/server.sock"
 
+// buildVersion is set by scripts/release for published artifacts.
+var buildVersion = "dev"
+
 func main() {
 	if err := run(os.Args[1:], os.Stdout, os.Stderr); err != nil {
 		fmt.Fprintln(os.Stderr, "rvc:", err)
@@ -33,6 +36,10 @@ func main() {
 }
 
 func run(args []string, output, diagnostics io.Writer) error {
+	if len(args) == 1 && args[0] == "--version" {
+		_, err := fmt.Fprintln(output, buildVersion)
+		return err
+	}
 	if len(args) == 0 {
 		return errors.New("a command is required (stat or run)")
 	}

cmd/rvc/main_test.go

@@ -50,6 +50,14 @@ func TestGlobalRequestIDIsInjectedOnlyForMutations_HP_CTL_12(t *testing.T) {
 	}
 }
 
+func TestVersionDoesNotRequireControlSocket_HP_CTL_16(t *testing.T) {
+	t.Parallel()
+	var output, diagnostics bytes.Buffer
+	if err := run([]string{"--version"}, &output, &diagnostics); err != nil || output.String() != "dev\n" {
+		t.Fatalf("version = %q, %v", output.String(), err)
+	}
+}
+
 func TestRenderCommandStatShowsExpiryRetentionAndWindowsIdentity_HP_CTL_13(t *testing.T) {
 	t.Parallel()
 	expiry := time.Date(2026, 9, 6, 12, 0, 0, 0, time.UTC)