Fix Kiro tool schema defaults

internal/translator/kiro/openai/kiro_openai.go

@@ -314,7 +314,7 @@ func ConvertOpenAIToolsToKiroFormat(tools []map[string]interface{}) []KiroToolWr
 
 		name := kirocommon.GetString(fn, "name")
 		description := kirocommon.GetString(fn, "description")
-		parameters := fn["parameters"]
+		parameters := ensureKiroInputSchema(fn["parameters"])
 
 		if name == "" {
 			continue
@@ -368,4 +368,4 @@ func ConvertClaudeToolUseToOpenAI(toolUseID, toolName string, input map[string]i
 // LogStreamEvent logs a streaming event for debugging
 func LogStreamEvent(eventType, data string) {
 	log.Debugf("kiro-openai: stream event type=%s, data_len=%d", eventType, len(data))
-}
+}