Pipeline Editor: Remember if user chooses source code editor and allow user to set a default editor

## What?

Pipeline Editor: Remember if user chooses source code editor and allow user to set a default editor

## Why?

While the Pipeline Editor UI is great, there are times where you will need to build a rule using the existing text editor. The process to switch from the Editor UI to text editor now requires 2 extra clicks and adds a lot of friction from a UX perspective:

1. Click 'Use Source Code Editor'
2. Click Confirm

Additionally this confirm box shouldn't appear if the user has not modified any of the input boxes for the editor UI since there are no unsaved changes that will be lost.

## Your Environment

* Graylog Version: 5.2.1
* OpenSearch Version: 2.11.1
* MongoDB Version: 6.0.11
* Operating System: Ubuntu Server 22.04 LTS
* Browser version: Google Chrome Version 120.0.6099.62 (Official Build) (arm64)

Please let me know if there are any questions. Thanks!