fix: resolve all nlreturn linter errors

Add blank lines before return statements in all files to satisfy
the nlreturn linter. This improves code readability by providing
visual separation before return statements.

Changes made across 24 files:
- internal/cli/*.go
- internal/secret/*.go
- internal/vault/*.go
- pkg/agehd/agehd.go
- pkg/bip85/bip85.go

All 143 nlreturn issues have been resolved.

internal/cli/secrets.go

@@ -135,6 +135,7 @@ func (cli *Instance) AddSecret(secretName string, force bool) error {
 	secret.Debug("Calling vault.AddSecret", "secret_name", secretName, "value_length", len(value), "force", force)
 	if err := vlt.AddSecret(secretName, value, force); err != nil {
 		secret.Debug("vault.AddSecret failed", "error", err)
+
 		return err
 	}
 
@@ -156,6 +157,7 @@ func (cli *Instance) GetSecretWithVersion(cmd *cobra.Command, secretName string,
 	vlt, err := vault.GetCurrentVault(cli.fs, cli.stateDir)
 	if err != nil {
 		secret.Debug("Failed to get current vault", "error", err)
+
 		return err
 	}
 
@@ -168,6 +170,7 @@ func (cli *Instance) GetSecretWithVersion(cmd *cobra.Command, secretName string,
 	}
 	if err != nil {
 		secret.Debug("Failed to get secret", "error", err)
+
 		return err
 	}