Fix enable_audit_log configuration not taking effect

The audit log configuration (enable_audit_log) was not taking effect
because the configuration values were stored as static final fields
in AbstractAuditLogger, which were initialized at class loading time
before the configuration file was fully loaded.

This fix changes the static final fields to dynamic method calls:
- IS_AUDIT_LOG_ENABLED -> isAuditLogEnabled()
- AUDITABLE_OPERATION_TYPE -> getAuditableOperationType()
- AUDITABLE_OPERATION_LEVEL -> getAuditableOperationLevel()
- AUDITABLE_OPERATION_RESULT -> getAuditableOperationResult()

This ensures that the configuration values are read dynamically
at runtime, after the configuration file has been properly loaded.

Fixes: #16706

Author: zhan7236

iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/audit/CNAuditLogger.java

@@ -42,5 +42,9 @@ public CNAuditLogger(ConfigManager configManager) {
   }
 
   @Override
-  public void log(IAuditEntity auditLogFields, Supplier<String> log) {}
+  public void log(IAuditEntity auditLogFields, Supplier<String> log) {
+    if (!isAuditLogEnabled()) {
+      return;
+    }
+  }
 }

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/audit/DNAuditLogger.java

@@ -57,10 +57,18 @@ private static InsertRowStatement generateInsertStatement(
   public void createViewIfNecessary() {}
 
   @Override
-  public synchronized void log(IAuditEntity auditLogFields, Supplier<String> log) {}
+  public synchronized void log(IAuditEntity auditLogFields, Supplier<String> log) {
+    if (!isAuditLogEnabled()) {
+      return;
+    }
+  }
 
   public void logFromCN(AuditLogFields auditLogFields, String log, int nodeId)
-      throws IllegalPathException {}
+      throws IllegalPathException {
+    if (!isAuditLogEnabled()) {
+      return;
+    }
+  }
 
   private static class DNAuditLoggerHolder {
 

iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/audit/AbstractAuditLogger.java

@@ -40,7 +40,16 @@ public abstract class AbstractAuditLogger {
   public static final String AUDIT_LOG_LOG = "log";
 
   private static final CommonConfig CONFIG = CommonDescriptor.getInstance().getConfig();
-  protected static final boolean IS_AUDIT_LOG_ENABLED = CONFIG.isEnableAuditLog();
+
+  /**
+   * Check if audit log is enabled. This method reads the configuration dynamically instead of using
+   * a static final field to ensure that the configuration is properly loaded before being used.
+   *
+   * @return true if audit log is enabled, false otherwise
+   */
+  protected static boolean isAuditLogEnabled() {
+    return CONFIG.isEnableAuditLog();
+  }
 
   public abstract void log(IAuditEntity auditLogFields, Supplier<String> log);