Add enterprise-grade standards to scripts

- Add copyright headers to all validation scripts
- Add usage/help functions to user-facing scripts
- Enhance common.sh with dependency checking and timestamps
- Add ENTERPRISE.md with comprehensive standards documentation
- Update scripts/README.md with enterprise features section
- Improve error messages and exit code handling

Co-authored-by: jmiller-moko <230051081+jmiller-moko@users.noreply.github.com>

scripts/validate/php_syntax.sh

@@ -1,4 +1,38 @@
 #!/usr/bin/env bash
+
+# ============================================================================
+# Copyright (C) 2025 Moko Consulting <hello@mokoconsulting.tech>
+#
+# This file is part of a Moko Consulting project.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program (./LICENSE.md).
+# ============================================================================
+
+# ============================================================================
+# FILE INFORMATION
+# ============================================================================
+# DEFGROUP: Script.Validate
+# INGROUP: Code.Quality
+# REPO: https://github.com/mokoconsulting-tech/moko-cassiopeia
+# PATH: /scripts/validate/php_syntax.sh
+# VERSION: 01.00.00
+# BRIEF: Validates PHP syntax using php -l on all PHP files
+# NOTE: Requires PHP CLI to be available
+# ============================================================================
+
 set -euo pipefail
 
 SRC_DIR="${SRC_DIR:-src}"