sync: update mage-x to v1.18.1 and remove deprecated test action (#234)

Author: mrz1836

.github/.env.base

@@ -235,7 +235,7 @@ REDIS_CACHE_FORCE_PULL=false           # Force pull Redis images even when cache
 # 🪄 MAGE-X CONFIGURATION
 # ================================================================================================
 
-MAGE_X_VERSION=v1.18.0                                        # https://github.com/mrz1836/mage-x/releases
+MAGE_X_VERSION=v1.18.1                                        # https://github.com/mrz1836/mage-x/releases
 MAGE_X_USE_LOCAL=false                                        # Use local version for development
 MAGE_X_CI_SKIP_STEP_SUMMARY=true                              # Skip duplicate test results in step summary (already in test validation summary)
 MAGE_X_AUTO_DISCOVER_BUILD_TAGS=true                          # Enable auto-discovery of build tags
@@ -509,5 +509,10 @@ GO_BROADCAST_AI_RETRY_MAX_ATTEMPTS=3
 GO_BROADCAST_AI_RETRY_INITIAL_DELAY=1
 GO_BROADCAST_AI_RETRY_MAX_DELAY=10
 
+# Error handling behavior
+# When true, AI failures will cause sync to fail with an error (shows which API key env var was used)
+# When false (default), AI failures silently fall back to static templates
+GO_BROADCAST_AI_FAIL_ON_ERROR=false
+
 # Diff Debugging
 # GO_BROADCAST_DEBUG_DIFF_PATH=/tmp/debug-diff.txt