Apply mechanical lint fixes for golangci-lint v2.12.2 rollout

Auto-remediate style-only findings (wsl_v5, nlreturn, noinlineerr,
modernize, intrange, perfsprint, usetesting, unconvert, errorlint,
gocritic, testifylint) and rename printf-style helpers to f-suffixed
names (goprintffuncname): ui.Writer message methods, cli.ReportErrorf,
database.Fatalf, vaultik stdoutf.

internal/cli/root.go

@@ -78,6 +78,7 @@ func ResolveConfigPath() (string, error) {
 		if _, err := os.Stat(path); err != nil {
 			return "", fmt.Errorf("config file from --config not found: %s (run 'vaultik config init --config %s' to create it)", path, path)
 		}
+
 		return path, nil
 	}
 
@@ -85,6 +86,7 @@ func ResolveConfigPath() (string, error) {
 		if _, err := os.Stat(path); err != nil {
 			return "", fmt.Errorf("config file from $VAULTIK_CONFIG not found: %s (unset VAULTIK_CONFIG, point it at an existing file, or run 'vaultik config init')", path)
 		}
+
 		return path, nil
 	}
 
@@ -114,5 +116,6 @@ func DefaultConfigPath() string {
 	if os.Getuid() == 0 {
 		return "/etc/vaultik/config.yml"
 	}
+
 	return filepath.Join(xdg.ConfigHome, "vaultik", "config.yml")
 }