fix: log management race condition, partial delete reporting, and UX issues

- Fix data race on gin.DefaultWriter during log rotation by adding LogWriterMu
- Report partial failure when some log files fail to delete instead of always returning success
- Fix misleading "logging disabled" banner shown before API responds
- Fix en.json translation for numeric validation message

logger/logger.go

@@ -61,12 +61,15 @@ func SetupLogger() {
 		oldFile := currentLogFile
 		currentLogPath = logPath
 		currentLogFile = fd
+		currentLogPathMu.Unlock()
+
+		common.LogWriterMu.Lock()
 		gin.DefaultWriter = io.MultiWriter(os.Stdout, fd)
 		gin.DefaultErrorWriter = io.MultiWriter(os.Stderr, fd)
-		currentLogPathMu.Unlock()
 		if oldFile != nil {
 			_ = oldFile.Close()
 		}
+		common.LogWriterMu.Unlock()
 	}
 }
 
@@ -92,16 +95,18 @@ func LogDebug(ctx context.Context, msg string, args ...any) {
 }
 
 func logHelper(ctx context.Context, level string, msg string) {
-	writer := gin.DefaultErrorWriter
-	if level == loggerINFO {
-		writer = gin.DefaultWriter
-	}
 	id := ctx.Value(common.RequestIdKey)
 	if id == nil {
 		id = "SYSTEM"
 	}
 	now := time.Now()
+	common.LogWriterMu.RLock()
+	writer := gin.DefaultErrorWriter
+	if level == loggerINFO {
+		writer = gin.DefaultWriter
+	}
 	_, _ = fmt.Fprintf(writer, "[%s] %v | %s | %s \n", level, now.Format("2006/01/02 - 15:04:05"), id, msg)
+	common.LogWriterMu.RUnlock()
 	logCount++ // we don't need accurate count, so no lock here
 	if logCount > maxLogCount && !setupLogWorking {
 		logCount = 0