Supports generating Elasticsearch indices daily and creating an alias for them.

Writing all log data to a single Elasticsearch index can result in a very large index. Splitting the index by day and creating an alias allows for reducing the data volume in each individual index and enabling queries through the alias.

for example. today is 2025-03-31. the index name were set to be shenyu-access-logging. the real index to write to will be shenyu-access-logging-2025-03-31. and will create alias for shenyu-access-logging-2025-03-31, so user can search shenyu-access-logging

Make sure that:

• You have read the contribution guidelines.
• You submit test cases (unit or integration tests) that back your changes.
• Your local test passed ./mvnw clean install -Dmaven.javadoc.skip=true.