Feature: support Global prefix_filter for All Logs

[youngsofun]

Current Behavior

Currently, the prefix_filter configuration is only supported for file logs. However, when a user enables this configuration, they likely expect it to apply to all log outputs, not just file logs.

Proposed Enhancement

Introduce a global prefix_filter configuration that applies to all logs. The existing prefix_filter for file logs can be retained for finer control, and it will override the global prefix_filter if specified. This approach ensures backward compatibility while making the configuration more intuitive.

Compatibility

• The default value for the global prefix_filter will remain "databend_,openraft", maintaining existing behavior.
• Setting the prefix_filter to an empty string will allow all log targets to be included.

Benefits

• Simplifies log configuration for users by reducing the need to duplicate filters across different log types.
• Retains fine-grained control for file-specific log filters when needed.
• Provides a more consistent behavior for logging across the system.

Example

[log]
prefix_filter = "databend_"  # new config

[log.file]
level = "DEBUG"
format = "text"
dir = "./.databend/logs_1"
prefix_filter = "databend_,openraft" 

[youngsofun]

cc @wubx

[Xuanwo]

Hi, this got me thinking about whether RUST_LOG itself supports filtering: https://docs.rs/env_logger/latest/env_logger/#enabling-logging

Perhaps we could simply extend the support for levels and pass it down to the underlying logging tools?

For example:

[log.file]
level = "DEBUG,databend_query=info"