Add option for default `log_source` setting in task logs web UI

[zach-overflow]

Description

Currently, any task log page on the web UI shows a dropdown to select the log source, with the default always being All Sources.

Ideally it would be great if there were an Airflow config setting like api.default_ui_log_source, which may optionally be set to any one of the following standard options:

• "operator"
• "task"
• "task.stderr"
• "All Sources"
• "airflow.plugins_manager"

If the config is not set, then the log_source value in the web UI defaults to the All Sources option as it currently does in Airflow 3.1.8.

Use case/motivation

For many of our users, the majority of the log sources emanating from the "All Sources" option are irrelevant, or confusing (for example, logs from the plugin manager bootstrapping are typically not useful to many data practictioners).

Also, it is common for much of the non-task log sources to be repeated across task instances and dag runs, regardless of the task or dag in question. Again, this is particularly true for things like plugin bootstrapping.

Related issues

Not any that I'm aware of.

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct