version promote --help says the current file is rewritten (closes #153)

The help text for `secret version promote` and a comment in
PromoteVersion said promote updates a "current symlink". `current` is a
plain file holding the version name, and promote rewrites it; the README
already says so. A new test runs `secret version promote --help` and
checks the output does not mention a symlink and does name the current
file.

Model: opus-5-5

internal/cli/version_test.go

@@ -6,6 +6,8 @@
 // - TestListVersionsNonExistentSecret: Tests error handling for missing secrets
 // - TestPromoteVersionCommand: Tests `secret version promote` command
 // - TestPromoteNonExistentVersion: Tests error handling for invalid promotion
+// - TestPromoteHelpSaysCurrentFileIsRewritten: Tests `secret version promote
+//   --help` text
 // - TestGetSecretWithVersion: Tests `secret get --version` flag functionality
 // - TestGetSecretWritesBinaryValue: Tests `secret get` output of binary values
 // - TestGetSecretReturnsWriteError: Tests `secret get` when stdout fails
@@ -270,6 +272,23 @@ func TestPromoteNonExistentVersion(t *testing.T) {
 	require.ErrorIs(t, err, vault.ErrVersionNotFound)
 }
 
+// TestPromoteHelpSaysCurrentFileIsRewritten is a regression test for
+// https://git.eeqj.de/sneak/secret/issues/153: `secret version promote
+// --help` said it updates a symlink, but promote rewrites the secret's
+// `current` file, which is a plain file.
+//
+//nolint:paralleltest // executes the CLI in-process and sets the environment
+func TestPromoteHelpSaysCurrentFileIsRewritten(t *testing.T) {
+	env := map[string]string{secret.EnvStateDir: t.TempDir()}
+
+	output, err := ExecuteCommandInProcess(
+		[]string{"version", "promote", "--help"}, "", env)
+	require.NoError(t, err)
+
+	assert.NotContains(t, output, "symlink")
+	assert.Contains(t, output, "current file")
+}
+
 func TestGetSecretWithVersion(t *testing.T) {
 	t.Parallel()