chore: refactor agent configurations and update testing instructions

- Updated QA Security agent to use GPT-5.2-Codex and expanded toolset for enhanced functionality.
- Revised Supervisor agent to utilize GPT-5.2-Codex and improved toolset for code review processes.
- Modified architecture instructions to specify running Playwright tests with Firefox.
- Adjusted copilot instructions to run Playwright tests with Firefox as the default browser.
- Created documentation for coding best practices to ensure consistency and quality in project documentation.
- Established HTML/CSS style color guide to maintain accessible and professional design standards.
- Updated Playwright TypeScript instructions to reflect the change in default browser to Firefox.
- Enhanced testing instructions to clarify integration testing processes and default browser settings.
- Updated integration test scripts to align with CI workflows and improve clarity in execution.
- Created new integration test scripts for Cerberus, rate limiting, and WAF functionalities.
- Adjusted E2E testing scripts to default to Firefox and updated documentation accordingly.
- Modified GitHub Actions workflow to run the comprehensive integration test suite.

.github/skills/integration-test-cerberus-scripts/run.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Integration Test Cerberus - Wrapper Script
+# Tests Cerberus full-stack integration
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "${SCRIPT_DIR}/../../.." && pwd)"
+
+exec "${PROJECT_ROOT}/scripts/cerberus_integration.sh" "$@"