[Sync] Update project files from source repository (02e7266)

[mrz1836]

What Changed

• Updated MAGE_X_VERSION from v1.18.0 to v1.18.1 in .github/.env.base
• Added new configuration variable GO_BROADCAST_AI_FAIL_ON_ERROR=false with documentation explaining AI error handling behavior (when true, AI failures cause sync to fail; when false, failures silently fall back to static templates)
• Removed deprecated GitHub Action file .github/actions/test-statistics/action.yml (371 lines removed) - deprecation notice indicates this was replaced by magex native CI mode which auto-produces .mage-x/ci-results.jsonl
• Removed .github/workflows/fortress-test-fuzz.yml workflow file

Why It Was Necessary

• Upgrading to latest mage-x patch release to incorporate bug fixes or improvements
• Adding explicit error handling configuration for AI broadcast functionality provides control over failure behavior and debugging capabilities
• Removing deprecated test statistics action eliminates maintenance burden since magex CI mode now handles test result collection natively
• Cleaning up unused workflow files reduces CI complexity

Testing Performed

• Verify mage-x v1.18.1 is compatible with existing CI pipelines
• Confirm GO_BROADCAST_AI_FAIL_ON_ERROR=false default behavior maintains backward compatibility with existing AI broadcast workflows
• Validate that remaining workflows continue to function without the removed test-statistics action
• Ensure magex CI mode properly generates ci-results.jsonl as replacement for deprecated statistics collection

Impact / Risk

• Low Risk: Patch version bump for mage-x should be backward compatible
• Configuration Default: New AI error flag defaults to false, maintaining existing silent fallback behavior - no breaking changes expected
• Deprecated Code Removal: Workflows already migrated to magex native CI mode; removed action was kept only for backwards compatibility and is no longer actively used
• CI Simplification: Fewer workflow files and actions reduce maintenance surface area